diff --git a/install.sql b/install.sql
index 91446f5..cb0995a 100644
--- a/install.sql
+++ b/install.sql
@@ -6,6 +6,9 @@ CREATE TABLE IF NOT EXISTS `#__virtuemart_shipment_plg_zasilkovna` (
 	`zasilkovna_packet_id` decimal(10,0),
 	`zasilkovna_packet_price` decimal(15,2),
 	`weight` decimal(10,4),
+	`length` smallint unsigned,
+	`width` smallint unsigned,
+	`height` smallint unsigned,
 	`branch_id` decimal(10,0),
 	`branch_currency` char(5),
 	`branch_name_street` varchar(500),
diff --git a/install.zasilkovna.php b/install.zasilkovna.php
index 1b88a0e..a78b45e 100644
--- a/install.zasilkovna.php
+++ b/install.zasilkovna.php
@@ -1,6 +1,7 @@
 <?php
 
 use Joomla\CMS\Installer\Adapter\PluginAdapter;
+use VirtueMartModelZasilkovna\ConfigConstants;
 
 // No direct access to this file
 defined('_JEXEC') or die('Restricted access');
@@ -203,7 +204,7 @@ public function postflight($route, $adapter)
             require_once VMPATH_ROOT . '/plugins/vmshipment/zasilkovna/zasilkovna.php';
         }
 
-        $this->createCronToken();
+        $this->createConfigurationDefaults();
         if ($route === 'update' && $this->fromVersion && version_compare($this->fromVersion, '1.2.0', '<')) {
             $this->migratePricingRules();
         }
@@ -592,11 +593,11 @@ private function removeAdministratorFiles() {
     }
 
     /**
-     * Creates update carriers token.
+     * Creates update carriers token and other plugin configuration defaults.
      *
      * @return void
      */
-    private function createCronToken() {
+    private function createConfigurationDefaults(): void {
         /** @var \VirtueMartModelZasilkovna $model */
         $model = VmModel::getModel('zasilkovna');
         $config = $model->loadConfig();
@@ -605,6 +606,12 @@ private function createCronToken() {
             $config['cron_token'] = substr(sha1(rand()), 0, 16);
         }
 
+        foreach (ConfigConstants::CONFIG_DEFAULTS as $key => $value) {
+            if (!array_key_exists($key, $config)) {
+                $config[$key] = $value;
+            }
+        }
+
         $model->updateConfig($config);
     }
 
diff --git a/media/admin/com_virtuemart/controllers/zasilkovna.php b/media/admin/com_virtuemart/controllers/zasilkovna.php
index 062745a..7fa90c9 100644
--- a/media/admin/com_virtuemart/controllers/zasilkovna.php
+++ b/media/admin/com_virtuemart/controllers/zasilkovna.php
@@ -70,25 +70,18 @@ public function updateCarriers()
 
     /**
      * Handle the save task.
-     * @param int $data
+     * @param mixed $data
      * @throws Exception
      */
-    public function save($data = 0)
+    public function save($data = 0): void
     {
         vRequest::vmCheckToken();
-        $data = vRequest::getPost();
-        $message = null;
-
-        /** @var VirtueMartModelZasilkovna $model */
-        $model = VmModel::getModel('zasilkovna');
-        $currentData = $model->loadConfig();
-
-        if (strlen($data['zasilkovna_api_pass']) !== 32) {
-            $message = new FlashMessage(JText::_('PLG_VMSHIPMENT_PACKETERY_API_PASS_INVALID'), FlashMessage::TYPE_ERROR);
-        } else {
-            $model->updateConfig(array_replace_recursive($currentData, $data));
+        if ($data === 0) {
+            $data = vRequest::getPost();
         }
 
+        $message = $this->updateZasilkovnaConfig($data);
+
         $redir = 'index.php?option=com_virtuemart';
         $app = JFactory::getApplication();
         if ($app->input->getString('task') === 'apply') {
@@ -295,4 +288,49 @@ private function getExportOrders()
     {
         return isset($_POST['exportOrders']) && is_array($_POST['exportOrders']) ? $_POST['exportOrders'] : [];
     }
+
+    /**
+     * @param array<string, mixed> $data
+     * @return FlashMessage
+     */
+    private function updateZasilkovnaConfig(array $data): FlashMessage
+    {
+        $configStorage = new VirtueMartModelZasilkovna\ConfigSessionStorage(JFactory::getSession(), 'packeteryConfig');
+
+        /** @var VirtueMartModelZasilkovna $model */
+        $model = VmModel::getModel('zasilkovna');
+        $currentData = $model->loadConfig();
+
+        $formValidator = new VirtueMartModelZasilkovna\ConfigurationValidator($data);
+        $formValidator->validate();
+
+        if (!$formValidator->isValid()) {
+            $configStorage->write($data);
+            $errors = $formValidator->getErrors();
+            $messages = [];
+
+            //$error is either error string translation key, or array where 1st element is sprintf template and others are sprintf arguments (all untranslated)
+            foreach ($errors as $formField => $error) {
+                if (!is_array($error)) {
+                    $messages[] = JText::_($error);
+                } else {
+                    $messages[] = sprintf(
+                        JText::_($error[0]),
+                        ...array_map(
+                            static function ($item) {
+                                return JText::_($item);
+                            },
+                            array_slice($error, 1))
+                    );
+                }
+            }
+
+            return  new FlashMessage(implode("<br>", $messages), FlashMessage::TYPE_ERROR);
+        }
+
+        $model->updateConfig(array_replace_recursive($currentData, $formValidator->normalize()));
+        $configStorage->flush();
+
+        return  new FlashMessage(JText::_('PLG_VMSHIPMENT_PACKETERY_CONFIG_SAVED'), FlashMessage::TYPE_MESSAGE);
+    }
 }
diff --git a/media/admin/com_virtuemart/models/zasilkovna.php b/media/admin/com_virtuemart/models/zasilkovna.php
index d4d2095..23360fc 100644
--- a/media/admin/com_virtuemart/models/zasilkovna.php
+++ b/media/admin/com_virtuemart/models/zasilkovna.php
@@ -5,6 +5,8 @@
  * @link http://www.zasilkovna.cz
  */
 
+use VirtueMartModelZasilkovna\ConfigConstants;
+
 defined('_JEXEC') or die('Restricted access');
 
 if(!class_exists('VmModel')) require(VMPATH_ADMIN . DS . 'helpers' . DS . 'vmmodel.php');
@@ -16,7 +18,7 @@
  */
 class VirtueMartModelZasilkovna extends VmModel
 {
-    const VERSION = '1.4.0';
+    const VERSION = '2.0.0';
     const PLG_NAME = 'zasilkovna';
 
     const MAX_WEIGHT_DEFAULT = 5;
@@ -58,8 +60,8 @@ public function __construct()
 
         $this->config = $this->loadConfig();
 
-        $this->api_pass = isset($this->config['zasilkovna_api_pass']) ? $this->config['zasilkovna_api_pass'] : '';
-        $this->api_key = isset($this->config['zasilkovna_api_pass']) ? substr($this->config['zasilkovna_api_pass'], 0, 16) : '';
+        $this->api_pass = $this->config[ConfigConstants::KEY_API_PASS] ?? '';
+        $this->api_key = isset($this->config[ConfigConstants::KEY_API_PASS]) ? substr($this->config[ConfigConstants::KEY_API_PASS], 0, 16) : '';
         $this->_media_url = JURI::root(true) . "/media/com_zasilkovna/media/";
         $this->_media_path = JPATH_SITE . DS . "media" . DS . "com_zasilkovna" . DS . "media" . DS;
 
diff --git a/media/admin/com_virtuemart/models/zasilkovna_orders.php b/media/admin/com_virtuemart/models/zasilkovna_orders.php
index 24c369d..929a340 100644
--- a/media/admin/com_virtuemart/models/zasilkovna_orders.php
+++ b/media/admin/com_virtuemart/models/zasilkovna_orders.php
@@ -14,6 +14,7 @@
 
 if(!class_exists('VmModel')) require(JPATH_VM_ADMINISTRATOR . DS . 'helpers' . DS . 'vmmodel.php');
 
+use VirtueMartModelZasilkovna\ConfigConstants;
 use VirtueMartModelZasilkovna\Label;
 
 /**
@@ -158,7 +159,13 @@ public function printCarrierLabels(array $packetIds, Label\Format $format, $offs
         exit;
     }
 
-    public function submitToZasilkovna($orders_id_arr) {
+    /**
+     * @param string[] $orders_id_arr
+     * @return array<string,array<string,mixed>>
+     * @throws Exception
+     */
+    public function submitToZasilkovna(array $orders_id_arr): array
+    {
 
         $db = JFactory::getDBO();
         $gw = new SoapClient(VirtueMartModelZasilkovna::PACKETA_WSDL);
@@ -185,10 +192,20 @@ public function submitToZasilkovna($orders_id_arr) {
                     'value' => $order['value'],
                     'weight' => $order['weight'],
                     'currency' => $order['currency'],
-                    'eshop' => $sender_label = $this->zas_model->getConfig('zasilkovna_eshop_label'),
+                    'eshop' => $sender_label = $this->zas_model->getConfig(ConfigConstants::KEY_ESHOP_LABEL),
                     'adultContent' => (int)$order['adult_content'] === 1,
                 );
 
+                $dimensions = ['length', 'width', 'height'];
+                $size = [];
+                foreach ($dimensions as $dimension) {
+                        $size[$dimension] = $order[$dimension];
+                }
+
+                if ($order['length']) {
+                    $attributes['size'] = $size;
+                }
+
                 if (!empty($order['carrier_point'])) {
                     $attributes['carrierPickupPoint'] = $order['carrier_point'];
                 }
@@ -307,7 +324,7 @@ public function exportToCSV($orders_id_arr) {
         }
 
         $exportedOrders = array();
-        $sender_label = $this->zas_model->getConfig('zasilkovna_eshop_label');
+        $sender_label = $this->zas_model->getConfig(ConfigConstants::KEY_ESHOP_LABEL);
 
         echo '"verze 5"'.PHP_EOL.PHP_EOL;
 
@@ -334,9 +351,9 @@ public function exportToCSV($orders_id_arr) {
                 $row['recipient_city'],
                 $row['recipient_zip'],
                 $row['carrier_point'],
-                $row['width'],
-                $row['height'],
-                $row['depth'],
+                $row['width'] ?? '',
+                $row['height'] ?? '',
+                $row['length'] ?? '',
             );
 
             echo "," . implode(',', $order) . PHP_EOL;
@@ -430,11 +447,16 @@ private function createConvertInstance() {
         }
     }
 
-    protected function prepareForExport($orders_arr)
+    /**
+     * @param string[] $orders_arr
+     * @return array<array<string,mixed>>
+     * @throws Exception
+     */
+    protected function prepareForExport(array $orders_arr): array
     {
         if (!$orders_arr)
         {
-            return;
+            return [];
         }
 
         $db = JFactory::getDBO();
@@ -444,16 +466,28 @@ protected function prepareForExport($orders_arr)
         }
 
         $ordersForINStatement = implode("','", $orderNumbers);
-        $q = "SELECT o.order_number,curr.currency_code_3 order_currency_name,
-        plg.zasilkovna_packet_price order_total,oi.first_name,oi.last_name,
-        oi_bt.email,IFNULL(oi.phone_1, oi_bt.phone_1) as phone_1,IFNULL(oi.phone_2, oi_bt.phone_2) as phone_2,plg.packet_cod,
-       	plg.branch_id,plg.zasilkovna_packet_id, plg.carrier_pickup_point, plg.is_carrier, 
-        plg.address as address, plg.adult_content AS adult_content, plg.city, plg.zip_code, plg.branch_currency, plg.weight FROM #__virtuemart_orders o ";
-        $q .= "INNER JOIN #__virtuemart_order_userinfos oi ON o.virtuemart_order_id=oi.virtuemart_order_id AND oi.address_type = IF(o.STsameAsBT = 1, 'BT', 'ST') ";
-        $q .= "INNER JOIN #__virtuemart_order_userinfos oi_bt ON o.virtuemart_order_id=oi_bt.virtuemart_order_id AND oi_bt.address_type = 'BT' ";
-        $q .= "INNER JOIN " . $this->zas_model->getDbTableName() . " plg ON plg.order_number=o.order_number ";
-        $q .= "LEFT JOIN #__virtuemart_currencies curr ON curr.virtuemart_currency_id=o.order_currency ";
-        $q .= " WHERE o.order_number IN ('" . $ordersForINStatement . "') GROUP BY o.order_number";
+
+        $q = sprintf(
+            "SELECT o.order_number, curr.currency_code_3 order_currency_name,
+                plg.zasilkovna_packet_price order_total, oi.first_name, oi.last_name,
+                oi_bt.email, IFNULL(oi.phone_1, oi_bt.phone_1) AS phone_1, IFNULL(oi.phone_2, oi_bt.phone_2) AS phone_2,
+                plg.packet_cod, plg.branch_id, plg.zasilkovna_packet_id, plg.carrier_pickup_point, plg.is_carrier,
+                plg.address AS address, plg.adult_content AS adult_content, plg.city, plg.zip_code, plg.branch_currency,
+                plg.weight, plg.width, plg.length, plg.height
+            FROM #__virtuemart_orders o
+            INNER JOIN #__virtuemart_order_userinfos oi 
+                ON o.virtuemart_order_id = oi.virtuemart_order_id AND oi.address_type = IF(o.STsameAsBT = 1, 'BT', 'ST')
+            INNER JOIN #__virtuemart_order_userinfos oi_bt 
+                ON o.virtuemart_order_id = oi_bt.virtuemart_order_id AND oi_bt.address_type = 'BT'
+            INNER JOIN %s plg ON plg.order_number = o.order_number
+            LEFT JOIN #__virtuemart_currencies curr ON curr.virtuemart_currency_id = o.order_currency
+            WHERE o.order_number IN ('%s') 
+            GROUP BY o.order_number
+            ",
+            $this->zas_model->getDbTableName(),
+            $ordersForINStatement
+        );
+
         $db->setQuery($q);
         $rows = $db->loadAssocList();
 
@@ -477,7 +511,6 @@ protected function prepareForExport($orders_arr)
                 $street = $streetMatches[1];
             }
 
-
             $phone = "";
             foreach (array('phone_2', 'phone_1') as $field)
             {
@@ -488,8 +521,8 @@ protected function prepareForExport($orders_arr)
                 }
             }
 
-			$orderForExport['order_number'] = $row['order_number'];
-			$orderForExport['recipient_firstname'] = $row['first_name'];
+            $orderForExport['order_number'] = $row['order_number'];
+            $orderForExport['recipient_firstname'] = $row['first_name'];
             $orderForExport['recipient_lastname'] = $row['last_name'];
             $orderForExport['recipient_company'] = "";
             $orderForExport['recipient_email'] = $row['email'];
@@ -506,9 +539,9 @@ protected function prepareForExport($orders_arr)
             $orderForExport['recipient_zip'] = $row['zip_code'];
             $orderForExport['carrier_point'] = $row['carrier_pickup_point'];
             $orderForExport['is_carrier'] = $row['is_carrier'];
-            $orderForExport['width'] = "";
-            $orderForExport['height'] = "";
-            $orderForExport['depth'] = "";
+            $orderForExport['width'] = $row['width'];
+            $orderForExport['height'] = $row['height'];
+            $orderForExport['length'] = $row['length'];
             $orderForExport['zasilkovna_packet_id'] = $row['zasilkovna_packet_id'];
 
             $ordersForExport[] = $orderForExport;
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Carrier/Repository.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Carrier/Repository.php
index 0296125..288f58f 100644
--- a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Carrier/Repository.php
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Carrier/Repository.php
@@ -101,11 +101,7 @@ public function getActiveHdCarriersForPublishedCountries()
         return $db->loadAssocList();
     }
 
-    /**
-     * @param int $carrierId
-     * @return null|\stdClass
-     */
-    public function getCarrierById($carrierId)
+    public function getCarrierById(int $carrierId): ?\stdClass
     {
         $db = \JFactory::getDBO();
         $db->setQuery(
@@ -114,6 +110,7 @@ public function getCarrierById($carrierId)
                    vzc.name, 
                    vzc.country, 
                    vzc.deleted,
+                   vzc.requires_size,
                    vc.virtuemart_country_id AS vm_country
                 FROM #__virtuemart_zasilkovna_carriers vzc
                 LEFT JOIN #__virtuemart_countries vc 
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigConstants.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigConstants.php
new file mode 100644
index 0000000..4dc8dd1
--- /dev/null
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigConstants.php
@@ -0,0 +1,27 @@
+<?php
+
+namespace VirtueMartModelZasilkovna;
+
+class ConfigConstants
+{
+    public const KEY_API_PASS = 'zasilkovna_api_pass';
+    public const KEY_ESHOP_LABEL = 'zasilkovna_eshop_label';
+    public const KEY_USE_DEFAULT_WEIGHT = 'zasilkovna_use_default_weight';
+    public const KEY_DEFAULT_WEIGHT = 'zasilkovna_default_weight';
+    public const KEY_USE_DEFAULT_DIMENSIONS = 'zasilkovna_use_default_dimensions';
+    public const KEY_DEFAULT_LENGTH = 'zasilkovna_default_length';
+    public const KEY_DEFAULT_WIDTH = 'zasilkovna_default_width';
+    public const KEY_DEFAULT_HEIGHT = 'zasilkovna_default_height';
+    public const KEY_PAYMENT_METHOD_PREFIX = 'zasilkovna_payment_method_';
+
+    public const CONFIG_DEFAULTS = [
+        self::KEY_USE_DEFAULT_WEIGHT => false,
+        self::KEY_DEFAULT_WEIGHT => '',
+        self::KEY_USE_DEFAULT_DIMENSIONS => false,
+        self::KEY_DEFAULT_LENGTH => '',
+        self::KEY_DEFAULT_WIDTH => '',
+        self::KEY_DEFAULT_HEIGHT => '',
+        self::KEY_API_PASS => '',
+        self::KEY_ESHOP_LABEL => '',
+    ];
+}
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigSessionStorage.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigSessionStorage.php
new file mode 100644
index 0000000..46ad199
--- /dev/null
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigSessionStorage.php
@@ -0,0 +1,31 @@
+<?php
+
+namespace VirtueMartModelZasilkovna;
+
+class ConfigSessionStorage extends SessionStorage
+{
+    private const ID = 'fromPost';
+    private const KEY = 'formValues';
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function read(): array
+    {
+        return $this->get(self::ID, self::KEY) ?? [];
+    }
+
+    /**
+     * @param array<string, mixed> $data
+     * @return void
+     */
+    public function write(mixed $data): void
+    {
+        $this->set(self::ID, self::KEY, $data);
+    }
+
+    public function flush(): void
+    {
+        $this->remove(self::ID, self::KEY);
+    }
+}
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigurationValidator.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigurationValidator.php
new file mode 100644
index 0000000..c848d05
--- /dev/null
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ConfigurationValidator.php
@@ -0,0 +1,122 @@
+<?php
+namespace VirtueMartModelZasilkovna;
+
+class ConfigurationValidator
+{
+    private const DIMENSIONS = [
+        ConfigConstants::KEY_DEFAULT_LENGTH => 'PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_LENGTH',
+        ConfigConstants::KEY_DEFAULT_WIDTH => 'PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_WIDTH',
+        ConfigConstants::KEY_DEFAULT_HEIGHT => 'PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_HEIGHT',
+    ];
+
+    /**
+     * @var array<string, mixed>
+     */
+    private array $formData;
+
+    /**
+     * @var array <string, string>|array<string, array<string>>
+     */
+    private array $errors = [];
+
+    /**
+     * @param array<string, mixed> $formData
+     */
+    public function __construct(array $formData)
+    {
+        $this->formData = $formData;
+    }
+
+    public function validate(): void {
+        $this->validateApiPassword();
+        $this->validateWeight();
+        $this->validateDimensions();
+    }
+
+private function validateWeight(): void {
+    if (
+        $this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT] !== ''
+        && (
+            !is_numeric($this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT])
+            || (float)$this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT] < 0.001
+        )
+    ) {
+        $this->errors[ConfigConstants::KEY_DEFAULT_WEIGHT] = [
+            'PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE',
+            'PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT',
+        ];
+
+        return;
+    }
+
+        if ($this->formData[ConfigConstants::KEY_USE_DEFAULT_WEIGHT] === '1' && empty($this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT])) {
+            $this->errors[ConfigConstants::KEY_DEFAULT_WEIGHT] = [
+                'PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_IS_REQUIRED',
+                'PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT',
+            ];
+        }
+    }
+
+    private function validateDimensions(): void {
+        foreach (self::DIMENSIONS as $field => $label) {
+            if ((!empty($this->formData[$field]) || $this->formData[$field] === '0')
+                && (!is_numeric($this->formData[$field]) || (int)$this->formData[$field] < 1)
+            ) {
+                $this->errors[$field] = ['PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE_INTEGER', $label];
+                continue;
+            }
+            if ($this->formData[ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS] === '1' && empty($this->formData[$field])) {
+                $this->errors[$field] = ['PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_IS_REQUIRED', $label];
+            }
+        }
+    }
+
+    private function validateApiPassword(): void {
+        if ($this->formData[ConfigConstants::KEY_API_PASS] === '') {
+            $this->errors[ConfigConstants::KEY_API_PASS] = 'PLG_VMSHIPMENT_PACKETERY_API_PASS_NOT_SET';
+            return;
+        }
+        if (strlen($this->formData[ConfigConstants::KEY_API_PASS]) !== 32) {
+            $this->errors[ConfigConstants::KEY_API_PASS] = 'PLG_VMSHIPMENT_PACKETERY_API_PASS_INVALID';
+        }
+    }
+
+    public function isValid(): bool {
+        return empty($this->errors);
+    }
+
+    /**
+     * @return array<string, string>|array<string, array<string>>
+     */
+    public function getErrors(): array {
+        return $this->errors;
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function normalize(): array {
+        
+        $normalizedData = [];
+        $normalizedData[ConfigConstants::KEY_API_PASS] = $this->formData[ConfigConstants::KEY_API_PASS];
+        $normalizedData[ConfigConstants::KEY_ESHOP_LABEL] = $this->formData[ConfigConstants::KEY_ESHOP_LABEL] ?? ConfigConstants::CONFIG_DEFAULTS[ConfigConstants::KEY_ESHOP_LABEL];
+
+        $normalizedData[ConfigConstants::KEY_USE_DEFAULT_WEIGHT] = $this->formData[ConfigConstants::KEY_USE_DEFAULT_WEIGHT] === '1';
+        $normalizedData[ConfigConstants::KEY_DEFAULT_WEIGHT] = is_numeric($this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT]) ? round((float)$this->formData[ConfigConstants::KEY_DEFAULT_WEIGHT], 3) : '';
+
+        $normalizedData[ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS] = $this->formData[ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS] === '1';
+        foreach (self::DIMENSIONS as $field => $label) {
+            $normalizedData[$field] = is_numeric($this->formData[$field]) ? (int)$this->formData[$field] : '';
+        }
+
+        $paymentMethods = array_filter(
+            $this->formData,
+            static function ($key) {
+                return str_starts_with($key, ConfigConstants::KEY_PAYMENT_METHOD_PREFIX);
+            },
+            ARRAY_FILTER_USE_KEY
+        );
+
+        return array_merge($normalizedData, $paymentMethods);
+    }
+}
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Order/Order.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Order/Order.php
index f6192b9..a7c95bf 100644
--- a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Order/Order.php
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/Order/Order.php
@@ -25,6 +25,12 @@ class Order
     /* @var float $weight */
     private $weight;
 
+    private ?int $length;
+
+    private ?int $width;
+
+    private ?int $height;
+
     /* @var float $branch_id */
     private $branch_id;
 
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/SessionStorage.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/SessionStorage.php
new file mode 100644
index 0000000..5a2c09f
--- /dev/null
+++ b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/SessionStorage.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace VirtueMartModelZasilkovna;
+
+class SessionStorage
+{
+
+    private string $namespace = 'packeterySession';
+
+    private \Joomla\CMS\Session\Session $session;
+
+    /**
+     * @param \Joomla\CMS\Session\Session $session
+     * @param ?string $namespace
+     */
+    public function __construct(\Joomla\CMS\Session\Session $session, string $namespace = null)
+    {
+        $this->session = $session;
+        if ($namespace) {
+            $this->namespace = $namespace;
+        }
+    }
+
+    /**
+     * @param int|string $id
+     * @param string $key
+     * @param mixed|null $default
+     * @return mixed
+     */
+    public function get(int|string $id, string $key, mixed $default = null): mixed
+    {
+        return $this->session->get($this->composeKey($id, $key), $default);
+    }
+
+    /**
+     * @param int|string $id
+     * @param string $key
+     * @param mixed $value
+     */
+    public function set(int|string $id, string $key, mixed $value): void
+    {
+        $this->session->set($this->composeKey($id, $key), $value);
+    }
+
+    /**
+     * @param int|string $id
+     * @param string $key
+     */
+    public function remove(int|string $id, string $key): void
+    {
+        $this->session->remove($this->composeKey($id, $key));
+    }
+
+    /**
+     * @param int|string $id
+     * @param string $key
+     * @return string
+     */
+    private function composeKey(int|string $id, string $key): string
+    {
+        if ($id === '' || $key === '') {
+            throw new \InvalidArgumentException('Id or key cannot be empty');
+        }
+
+        return $this->namespace . '.' . $id . '.' . $key;
+    }
+}
diff --git a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ShipmentMethodStorage.php b/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ShipmentMethodStorage.php
deleted file mode 100644
index a649a74..0000000
--- a/media/admin/com_virtuemart/models/zasilkovna_src/VirtueMartModelZasilkovna/ShipmentMethodStorage.php
+++ /dev/null
@@ -1,50 +0,0 @@
-<?php
-
-namespace VirtueMartModelZasilkovna;
-
-class ShipmentMethodStorage
-{
-    /** @var string */
-    private $namespace = 'packeteryShipmentMethods';
-
-    /** @var \Joomla\CMS\Session\Session */
-    private $session;
-
-    /**
-     * @param \Joomla\CMS\Session\Session $session
-     */
-    public function __construct(\Joomla\CMS\Session\Session $session)
-    {
-        $this->session = $session;
-    }
-
-    /**
-     * @param string|int $methodId
-     * @param string $key
-     * @param mixed $default
-     * @return mixed
-     */
-    public function get($methodId, $key, $default = null)
-    {
-        return $this->session->get($methodId . '.' . $key, $default, $this->namespace);
-    }
-
-    /**
-     * @param string|int $methodId
-     * @param string $key
-     * @param mixed $value
-     */
-    public function set($methodId, $key, $value)
-    {
-        $this->session->set($methodId . '.' . $key, $value, $this->namespace);
-    }
-
-    /**
-     * @param string|int $methodId
-     * @param string $key
-     */
-    public function clear($methodId, $key)
-    {
-        $this->session->clear($methodId . '.' . $key, $this->namespace);
-    }
-}
diff --git a/media/admin/com_virtuemart/views/zasilkovna/tmpl/default_config.php b/media/admin/com_virtuemart/views/zasilkovna/tmpl/default_config.php
index c5116f9..2cbd6a1 100644
--- a/media/admin/com_virtuemart/views/zasilkovna/tmpl/default_config.php
+++ b/media/admin/com_virtuemart/views/zasilkovna/tmpl/default_config.php
@@ -1,6 +1,7 @@
 <?php
 
 use VirtueMartModelZasilkovna\Box\Renderer;
+use VirtueMartModelZasilkovna\ConfigConstants;
 use VirtueMartModelZasilkovna\Order\Detail;
 
 defined('_JEXEC') || die('Restricted access');
@@ -8,6 +9,7 @@
 /** @var VirtueMartModelZasilkovna $model */
 $model = VmModel::getModel('zasilkovna');
 
+
 $renderer = new Renderer();
 $renderer->setTemplate(Detail::TEMPLATES_DIR . DS . 'card.php');
 
@@ -30,7 +32,7 @@
             <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_API_PASS'); ?>
         </th>
         <td class="pb-10 pl-3">
-            <?php echo VmHTML::input('zasilkovna_api_pass', $model->getConfig('zasilkovna_api_pass')); ?><br>
+            <?php echo VmHTML::input(ConfigConstants::KEY_API_PASS, $this->getFormValue(ConfigConstants::KEY_API_PASS)); ?><br>
             <?php echo JText::sprintf('PLG_VMSHIPMENT_PACKETERY_FIND_API_PASS_IN_CS', '<a href="https://client.packeta.com/support" target="_blank">','</a>'); ?><br>
             <?php echo JText::sprintf('PLG_VMSHIPMENT_PACKETERY_NO_ACCOUNT_REGISTER_HERE','<a href="https://client.packeta.com/registration" target=\"_blank\">', '</a>'); ?>
         </td>
@@ -40,7 +42,7 @@
             <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_ESHOP_LABEL')?>
         </th>
         <td class="pb-10 pl-3">
-            <?php echo VmHTML::input('zasilkovna_eshop_label', $model->getConfig('zasilkovna_eshop_label')); ?><br>
+            <?php echo VmHTML::input(ConfigConstants::KEY_ESHOP_LABEL, $this->getFormValue(ConfigConstants::KEY_ESHOP_LABEL)); ?><br>
             <?php echo JText::sprintf(
                 'PLG_VMSHIPMENT_PACKETERY_ESHOP_LABEL_DESC',
                 '<a href="https://client.packeta.com" target="_blank">',
@@ -64,13 +66,15 @@
 ob_start();
 ?>
 <table class="admintable">
-    <?php foreach ($this->paymentMethods as $paymentMethod) { ?>
+    <?php foreach ($this->paymentMethods as $paymentMethod) {
+        $field = ConfigConstants::KEY_PAYMENT_METHOD_PREFIX . $paymentMethod->virtuemart_paymentmethod_id;
+    ?>
         <tr>
             <th>
                 <?php echo $paymentMethod->payment_name; ?>
             </th>
             <td class="pl-3">
-                <?php echo VmHTML::checkbox('zasilkovna_payment_method_' . $paymentMethod->virtuemart_paymentmethod_id, $model->getConfig('zasilkovna_payment_method_' . $paymentMethod->virtuemart_paymentmethod_id, '0') ); ?>
+                <?php echo VmHTML::checkbox($field, $this->getFormValue($field, '0') ); ?>
             </td>
         </tr>
     <?php } ?>
@@ -79,9 +83,87 @@
 $codContent = ob_get_clean();
 
 ob_start();
+// Default weight and dimensions start
 ?>
+    <table class="admintable">
+        <tr>
+            <th>
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_WEIGHT'); ?>
+            </th>
+            <td class="pl-3">
+                <?php echo VmHTML::checkbox(ConfigConstants::KEY_USE_DEFAULT_WEIGHT, (bool)$this->getFormValue(ConfigConstants::KEY_USE_DEFAULT_WEIGHT)); ?>
+            </td>
+        </tr>
+        <tr>
+            <th class="pb-28">
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT'); ?>
+            </th>
+            <td class="pl-3 pb-28">
+                <input
+                    name="<?php echo ConfigConstants::KEY_DEFAULT_WEIGHT; ?>"
+                    type="number"
+                    min="0"
+                    step="0.001"
+                    value="<?php echo $this->getFormValue(ConfigConstants::KEY_DEFAULT_WEIGHT); ?>"
+                />
+            </td>
+        </tr>
+        <tr>
+            <th>
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_DIMENSIONS'); ?>
+            </th>
+            <td class="pl-3">
+                <?php echo VmHTML::checkbox(ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS, (bool)$this->getFormValue(ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS)); ?>
+            </td>
+        </tr>
+        <tr>
+            <th>
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_LENGTH'); ?>
+            </th>
+            <td class="pl-3">
+                <input
+                    name="<?php echo ConfigConstants::KEY_DEFAULT_LENGTH; ?>"
+                    type="number"
+                    min="0"
+                    step="1"
+                    value="<?php echo $this->getFormValue(ConfigConstants::KEY_DEFAULT_LENGTH); ?>"
+                />
+            </td>
+        </tr>
+        <tr>
+            <th>
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_WIDTH'); ?>
+            </th>
+            <td class="pl-3">
+                <input
+                    name="<?php echo ConfigConstants::KEY_DEFAULT_WIDTH; ?>"
+                    type="number"
+                    min="0"
+                    step="1"
+                    value="<?php echo $this->getFormValue(ConfigConstants::KEY_DEFAULT_WIDTH); ?>"
+                />
+            </td>
+        </tr>
+        <tr>
+            <th>
+                <?php echo JText::_('PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_HEIGHT'); ?>
+            </th>
+            <td class="pl-3">
+                <input
+                    name="<?php echo ConfigConstants::KEY_DEFAULT_HEIGHT; ?>"
+                    type="number"
+                    min="0"
+                    step="1"
+                    value="<?php echo $this->getFormValue(ConfigConstants::KEY_DEFAULT_HEIGHT); ?>"
+                />
+            </td>
+        </tr>
+    </table>
 
 <?php
+$weightDimensionsContent = ob_get_clean();
+ob_start();
+
 $renderer->setVariables([
     'title' => JText::_('PLG_VMSHIPMENT_PACKETERY_SETTINGS'),
     'icon' => 'cog',
@@ -95,3 +177,10 @@
     'content' => $codContent,
 ]);
 echo $renderer->renderToString();
+
+$renderer->setVariables([
+    'title' => JText::_('PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT_DIMENSIONS_TITLE'),
+    'icon' => 'cog',
+    'content' => $weightDimensionsContent,
+]);
+echo $renderer->renderToString();
diff --git a/media/admin/com_virtuemart/views/zasilkovna/view.html.php b/media/admin/com_virtuemart/views/zasilkovna/view.html.php
index 4de3ab6..12847c5 100644
--- a/media/admin/com_virtuemart/views/zasilkovna/view.html.php
+++ b/media/admin/com_virtuemart/views/zasilkovna/view.html.php
@@ -37,6 +37,14 @@
  */
 class VirtuemartViewZasilkovna extends VmViewAdmin {
 
+    public VirtueMartModelZasilkovna $model;
+    public \VirtueMartModelZasilkovna\ConfigSessionStorage $configStorage;
+    public function __construct($config = array()) {
+        parent::__construct($config);
+        $this->model = VmModel::getModel();
+        $this->configStorage = new \VirtueMartModelZasilkovna\ConfigSessionStorage(JFactory::getSession(),'packeteryConfig');
+    }
+
     function display($tpl = NULL) {
 
 
@@ -47,10 +55,7 @@ function display($tpl = NULL) {
 
         $configModel = VmModel::getModel('config');
 
-        /** @var VirtueMartModelZasilkovna $model */
-        $model = VmModel::getModel();
-
-        if(!$model->getConfig(VirtuemartControllerZasilkovna::ZASILKOVNA_LIMITATIONS_REMOVED_NOTICE_DISMISSED, false)) {
+        if(!$this->model->getConfig(VirtuemartControllerZasilkovna::ZASILKOVNA_LIMITATIONS_REMOVED_NOTICE_DISMISSED, false)) {
             $this->showLimitationsRemovedNotice();
         }
 
@@ -64,8 +69,8 @@ function cmpShipments($a, $b) {
         $this->shipmentMethods = $shipments;
 
         $this->moduleVersion = VirtueMartModelZasilkovna::VERSION;
-        $this->errors = $model->errors;
-        $this->warnings = $model->warnings;
+        $this->errors = $this->model->errors;
+        $this->warnings = $this->model->warnings;
 
         $paymentModel = VmModel::getModel('paymentmethod');
         $payments = $paymentModel->getPayments();
@@ -153,8 +158,9 @@ function cmpPayments($a, $b) {
         $this->pagination = $ordersModel->getPagination();
 
         $this->shipmentSelect = $this->renderShipmentsList();
-        $model->raiseErrors($mainframe);
+        $this->model->raiseErrors($mainframe);
         parent::display($tpl);
+        $this->configStorage->flush();
     }
 
     public function renderOrderstatesList() {
@@ -218,4 +224,22 @@ private function showLimitationsRemovedNotice()
         $app = JFactory::getApplication();
         $app->enqueueMessage($fullFlashMessage, \VirtueMartModelZasilkovna\FlashMessage::TYPE_NOTICE);
     }
+
+    /**
+     * @param string $name
+     * @param mixed $default
+     * @return array|mixed|string
+     */
+    public function getFormValue(string $name, mixed $default = ''): mixed
+    {
+        static $sessionData = null;
+
+        if ($sessionData === null) {
+            $sessionData = $this->configStorage->read();
+        }
+
+        $fromSession = $sessionData[$name] ?? null;
+
+        return $fromSession ?? $this->model->getConfig($name, $default);
+    }
 }
diff --git a/media/admin/cs-CZ.plg_vmshipment_zasilkovna.ini b/media/admin/cs-CZ.plg_vmshipment_zasilkovna.ini
index 94b3a05..e5fa6f0 100644
--- a/media/admin/cs-CZ.plg_vmshipment_zasilkovna.ini
+++ b/media/admin/cs-CZ.plg_vmshipment_zasilkovna.ini
@@ -129,3 +129,15 @@ PLG_VMSHIPMENT_PACKETERY_ORDER_DETAILS_UPDATED="Detaily objednávky byly aktuali
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUPS="Typy výdejních míst"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZPOINT="Výdejní místa"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZBOX="Z-Box"
+
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT_DIMENSIONS_TITLE="Výchozí hmotnost a rozměry zásilky"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_WEIGHT="Použít výchozí hmotnost"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT="Výchozí hmotnost (kg)"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_DIMENSIONS="Použít výchozí rozměry"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_WIDTH="Výchozí šířka (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_HEIGHT="Výchozí výška (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_LENGTH="Výchozí délka (mm)"
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE="Pole %s musí být kladné číslo."
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE_INTEGER="Pole %s musí být kladné celé číslo."
+PLG_VMSHIPMENT_PACKETERY_CONFIG_SAVED="Nastavení bylo uloženo."
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_IS_REQUIRED="Field %s is required."
diff --git a/media/admin/en-GB.plg_vmshipment_zasilkovna.ini b/media/admin/en-GB.plg_vmshipment_zasilkovna.ini
index 0dd6ff6..cddf8f8 100644
--- a/media/admin/en-GB.plg_vmshipment_zasilkovna.ini
+++ b/media/admin/en-GB.plg_vmshipment_zasilkovna.ini
@@ -129,3 +129,15 @@ PLG_VMSHIPMENT_PACKETERY_ORDER_DETAILS_UPDATED="Order details were updated."
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUPS="Groups"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZPOINT="Pickup points"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZBOX="Z-Box"
+
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT_DIMENSIONS_TITLE="Default packet weight and dimensions"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_WEIGHT="Use default weight"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT="Default weight (kg)"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_DIMENSIONS="Use default dimensions"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_WIDTH="Default width (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_HEIGHT="Default height (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_LENGTH="Default length (mm)"
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE="Field %s must be a positive number."
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE_INTEGER="Field %s must be a positive integer number."
+PLG_VMSHIPMENT_PACKETERY_CONFIG_SAVED="Configuration was saved."
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_IS_REQUIRED="Field %s is required."
diff --git a/media/admin/sk-SK.plg_vmshipment_zasilkovna.ini b/media/admin/sk-SK.plg_vmshipment_zasilkovna.ini
index 0b6bbde..3877eb0 100644
--- a/media/admin/sk-SK.plg_vmshipment_zasilkovna.ini
+++ b/media/admin/sk-SK.plg_vmshipment_zasilkovna.ini
@@ -130,3 +130,15 @@ PLG_VMSHIPMENT_PACKETERY_ORDER_DETAILS_UPDATED="Detaily objednávky byly aktuali
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUPS="Typy výdajných miest"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZPOINT="Výdajné miesta"
 PLG_VMSHIPMENT_PACKETERY_CONFIG_PICKUP_POINTS_GROUP_ZBOX="Z-Box"
+
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT_DIMENSIONS_TITLE="Výchozí hmotnost a rozměry zásilky"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_WEIGHT="Použít výchozí hmotnost"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_WEIGHT="Výchozí hmotnost (kg)"
+PLG_VMSHIPMENT_PACKETERY_USE_DEFAULT_DIMENSIONS="Použít výchozí rozměry"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_WIDTH="Výchozí šířka (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_HEIGHT="Výchozí výška (mm)"
+PLG_VMSHIPMENT_PACKETERY_DEFAULT_DIMENSIONS_LENGTH="Výchozí délka (mm)"
+PLG_VMSHIPMENT_PACKETERY_ENTER_POSITIVE_VALUE_IN_MM="zadejte kladnou hodnotu v mm"
+PLG_VMSHIPMENT_PACKETERY_ENTER_POSITIVE_VALUE_IN_KG="zadejte kladnou hodnotu v kg"
+PLG_VMPSHIPMENT_PACKETERY_DEFAULT_FIELD_MUST_BE_POSITIVE="Pole %s je povinné a musí být kladné číslo."
+PLG_VMSHIPMENT_PACKETERY_CONFIG_SAVED="Nastavení bylo uloženo."
diff --git a/media/media/css/admin.css b/media/media/css/admin.css
index 0e8f222..8398d49 100644
--- a/media/media/css/admin.css
+++ b/media/media/css/admin.css
@@ -45,6 +45,10 @@ fieldset {
     padding-bottom: 10px;
 }
 
+.pb-28 {
+    padding-bottom: 28px;
+}
+
 .va-middle {
     vertical-align: middle !important;
 }
diff --git a/zasilkovna.php b/zasilkovna.php
index 7b68e4d..d86eaa1 100644
--- a/zasilkovna.php
+++ b/zasilkovna.php
@@ -1,5 +1,6 @@
 <?php
 
+use VirtueMartModelZasilkovna\ConfigConstants;
 use VirtueMartModelZasilkovna\ShipmentMethod;
 use VirtueMartModelZasilkovna\Carrier\VendorGroups;
 
@@ -49,8 +50,7 @@ class plgVmShipmentZasilkovna extends vmPSPlugin
     /** @var \VirtueMartModelZasilkovna\CheckoutModuleDetector */
     protected $checkoutModuleDetector;
 
-    /** @var \VirtueMartModelZasilkovna\ShipmentMethodStorage */
-    private $shipmentMethodStorage;
+    private \VirtueMartModelZasilkovna\SessionStorage $shipmentMethodStorage;
 
     /** @var \VirtueMartModelZasilkovna\ShipmentMethodValidator */
     protected $shipmentMethodValidator;
@@ -91,7 +91,7 @@ public function __construct(&$subject, $config) {
         $this->model = VmModel::getModel('zasilkovna');
         $this->session = JFactory::getSession();
         $this->checkoutModuleDetector = new \VirtueMartModelZasilkovna\CheckoutModuleDetector();
-        $this->shipmentMethodStorage = new \VirtueMartModelZasilkovna\ShipmentMethodStorage($this->session);
+        $this->shipmentMethodStorage = new \VirtueMartModelZasilkovna\SessionStorage($this->session, 'packeteryShipmentMethods');
         $this->shipmentMethodValidator = new \VirtueMartModelZasilkovna\ShipmentMethodValidator();
         $this->orderDetail = new \VirtueMartModelZasilkovna\Order\Detail();
         $this->orderRepository = new \VirtueMartModelZasilkovna\Order\Repository();
@@ -235,22 +235,22 @@ public function plgVmOnShowOrderFEShipment($virtuemart_order_id, $virtuemart_shi
      * @param string|int $methodId
      */
     public function clearPickedDeliveryPoint($methodId) {
-        $this->shipmentMethodStorage->clear($methodId, 'branch_id');
-        $this->shipmentMethodStorage->clear($methodId, 'branch_currency');
-        $this->shipmentMethodStorage->clear($methodId, 'branch_name_street');
-        $this->shipmentMethodStorage->clear($methodId, 'branch_country');
-        $this->shipmentMethodStorage->clear($methodId, 'branch_carrier_id');
-        $this->shipmentMethodStorage->clear($methodId, 'branch_carrier_pickup_point');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_id');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_currency');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_name_street');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_country');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_carrier_id');
+        $this->shipmentMethodStorage->remove($methodId, 'branch_carrier_pickup_point');
     }
 
     /**
      * This event is fired after the order has been stored; it gets the shipment method-
      * specific data.
      *
-     * @return mixed Null when this method was not selected, otherwise true
+     * @return null|bool Null when this method was not selected, otherwise true
      * @author Valerie Isaksen
      */
-    function plgVmConfirmedOrder(VirtueMartCart $cart, $order) {
+    function plgVmConfirmedOrder(VirtueMartCart $cart, array $order): ?bool {
         if (!($method = $this->getVmPluginMethod($order['details']['BT']->virtuemart_shipmentmethod_id))) {
             return null; // Another method was selected, do nothing
         }
@@ -268,13 +268,18 @@ function plgVmConfirmedOrder(VirtueMartCart $cart, $order) {
 
         // GET PARAMETERS FROM SESSION AND CLEAR
         $branch_id = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id, 'branch_id', 0);
-        $branch_name_street = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id, 'branch_name_street', '');
-        $branch_carrier_id = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id, 'branch_carrier_id');
-        $branch_carrier_pickup_point = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id, 'branch_carrier_pickup_point');
+        $branch_name_street = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id,
+            'branch_name_street',
+            '');
+        $branch_carrier_id = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id, 'branch_carrier_id',
+            null);
+        $branch_carrier_pickup_point = $this->shipmentMethodStorage->get($cart->virtuemart_shipmentmethod_id,
+            'branch_carrier_pickup_point',
+            null);
 
         $this->clearPickedDeliveryPoint($cart->virtuemart_shipmentmethod_id);
 
-        $codSettings = $this->model->getConfig('zasilkovna_payment_method_'.$cart->virtuemart_paymentmethod_id, 0);
+        $codSettings = $this->model->getConfig(ConfigConstants::KEY_PAYMENT_METHOD_PREFIX . $cart->virtuemart_paymentmethod_id, 0);
 
         $billing=$order['details']['BT'];
         $shipping=$order['details']['ST'];
@@ -315,6 +320,7 @@ function plgVmConfirmedOrder(VirtueMartCart $cart, $order) {
         } else {
             $branch_id = $branch_carrier_id;
             $is_carrier = 1;
+            $carrier = $this->carrierRepository->getCarrierById($branch_id);
         }
 
         if ($zasMethod->isHdCarrier()) {
@@ -351,8 +357,29 @@ function plgVmConfirmedOrder(VirtueMartCart $cart, $order) {
         $values['exported'] = 0;
         $values['shipment_name'] = $method->shipment_name;
         $values['shipment_cost'] = $this->getCosts($cart, ShipmentMethod::fromRandom($method), "");
-        $values['weight'] = $this->getOrderWeight($cart, self::DEFAULT_WEIGHT_UNIT);
+        $weight = $this->getOrderWeight($cart, self::DEFAULT_WEIGHT_UNIT);
+
+        if (!$weight && $this->model->getConfig(ConfigConstants::KEY_USE_DEFAULT_WEIGHT) === true) {
+            $weight = (float)$this->model->getConfig(ConfigConstants::KEY_DEFAULT_WEIGHT);
+        }
+        $values['weight'] = $weight;
         $values['tax_id'] = $method->tax_id;
+
+        if ($is_carrier === 1
+            && $carrier
+            && $carrier->requires_size === 1
+            && $this->model->getConfig(ConfigConstants::KEY_USE_DEFAULT_DIMENSIONS) === true
+        ) {
+            $values['length'] = (int)$this->model->getConfig(ConfigConstants::KEY_DEFAULT_LENGTH);
+            $values['width'] = (int)$this->model->getConfig(ConfigConstants::KEY_DEFAULT_WIDTH);
+            $values['height'] = (int)$this->model->getConfig(ConfigConstants::KEY_DEFAULT_HEIGHT);
+        } else {
+            //empty string to force null in database
+            $values['length'] = '';
+            $values['width'] = '';
+            $values['height'] = '';
+        }
+
         $this->storePSPluginInternalData($values);
 
         return true;
@@ -697,7 +724,7 @@ public function plgVmOnCheckoutCheckDataShipment(VirtueMartCart $cart) {
      */
     public function hasPointSelected($methodId)
     {
-        $branchId = $this->shipmentMethodStorage->get($methodId, 'branch_id');
+        $branchId = $this->shipmentMethodStorage->get($methodId, 'branch_id', null);
         return !empty($branchId);
     }
 
@@ -824,7 +851,9 @@ public function plgVmDisplayListFEShipment(VirtueMartCart $cart, $selected = 0,
                         'baseHtml' => $baseHtml,
                         'isCountrySelected' => !empty($address['virtuemart_country_id']),
                         'savedBranchNameStreet' =>
-                            (string)$this->shipmentMethodStorage->get($method->virtuemart_shipmentmethod_id, 'branch_name_street', ''),
+                            (string)$this->shipmentMethodStorage->get($method->virtuemart_shipmentmethod_id,
+                                'branch_name_street',
+                                ''),
                     ]
                 );
 
@@ -943,7 +972,7 @@ public function plgVmOnUpdateCart(VirtueMartCart $cart) {
         }
 
         $countryCode = strtolower(ShopFunctions::getCountryByID($address['virtuemart_country_id'], 'country_2_code'));
-        $sessionCountry = $this->shipmentMethodStorage->get($virtuemartShipmentMethodId, 'branch_country');
+        $sessionCountry = $this->shipmentMethodStorage->get($virtuemartShipmentMethodId, 'branch_country', null);
         if ($sessionCountry && $countryCode !== $sessionCountry) {
             $this->clearPickedDeliveryPoint($virtuemartShipmentMethodId);
             $cart->virtuemart_shipmentmethod_id = null; // makes selected shipping method disappear
diff --git a/zasilkovna.xml b/zasilkovna.xml
index 1a13235..7eb7001 100644
--- a/zasilkovna.xml
+++ b/zasilkovna.xml
@@ -11,7 +11,7 @@
     <copyright>(c) 2021 Zásilkovna s.r.o.</copyright>
     <license>License Info with link</license>
     <!--  The version string is recorded in the components table -->
-    <version>1.4.0</version>
+    <version>2.0.0</version>
     <!--  The date for the actual version release -->
     <releaseDate>2021-06-29</releaseDate>
     <!--  Type of release: Bug fix, Security Fix, Minor update, Major update -->