diff --git a/hb_server/apps/wpm/serializers.py b/hb_server/apps/wpm/serializers.py
index 0ea78b3..d2d7cc2 100644
--- a/hb_server/apps/wpm/serializers.py
+++ b/hb_server/apps/wpm/serializers.py
@@ -182,7 +182,7 @@ class WProductDetailSerializer(serializers.ModelSerializer):
     def get_children(self, obj):
         wps = WProduct.objects.filter(child=obj)
         if wps.exists():
-            return WProductBaseSerializer(instance=wps, many=True)
+            return WProductBaseSerializer(instance=wps, many=True).data
         return []
 
 class OperationDetailSerializer(serializers.ModelSerializer):