diff --git a/autoload/api/Controllers/ProductsApiController.php b/autoload/api/Controllers/ProductsApiController.php
index c204635..738a13d 100644
--- a/autoload/api/Controllers/ProductsApiController.php
+++ b/autoload/api/Controllers/ProductsApiController.php
@@ -497,6 +497,21 @@ class ProductsApiController
             $d['products_related'] = $body['products_related'];
         }
 
+        // Custom fields (Dodatkowe pola)
+        if (isset($body['custom_fields']) && is_array($body['custom_fields'])) {
+            $d['custom_field_name']     = [];
+            $d['custom_field_type']     = [];
+            $d['custom_field_required'] = [];
+            foreach ($body['custom_fields'] as $cf) {
+                if (!is_array($cf) || empty($cf['name'])) {
+                    continue;
+                }
+                $d['custom_field_name'][]     = (string)$cf['name'];
+                $d['custom_field_type'][]     = isset($cf['type']) ? (string)$cf['type'] : 'text';
+                $d['custom_field_required'][] = !empty($cf['is_required']) ? 1 : 0;
+            }
+        }
+
         return $d;
     }
 }
diff --git a/docs/API.md b/docs/API.md
index 963de7f..5a5772b 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -302,11 +302,15 @@ Content-Type: application/json
     }
   },
   "categories": [1, 5],
-  "products_related": [10, 20]
+  "products_related": [10, 20],
+  "custom_fields": [
+    {"name": "Napis na koszulce", "type": "text", "is_required": 1}
+  ]
 }
 ```
 
 Wymagane: `languages` (min. 1 jezyk z `name`) oraz `price_brutto`.
+`custom_fields` — opcjonalne; kazdy element wymaga `name`, `type` (domyslnie `text`), `is_required` (0/1).
 
 Odpowiedz (HTTP 201):
 ```json
diff --git a/updates/versions.php b/updates/versions.php
index ac6b5c3..2f0b4de 100644
--- a/updates/versions.php
+++ b/updates/versions.php
@@ -1,5 +1,5 @@
 <?
-$current_ver = 320;
+$current_ver = 321;
 
 for ($i = 1; $i <= $current_ver; $i++)
 {