diff --git a/modules/purchase_trade/stock.py b/modules/purchase_trade/stock.py
index c6053f6..cff242b 100755
--- a/modules/purchase_trade/stock.py
+++ b/modules/purchase_trade/stock.py
@@ -27,6 +27,7 @@ import re
 import html
 from trytond.exceptions import UserError
 from trytond.modules.stock.shipment import SupplierShipping as BaseSupplierShipping
+from . import lot as purchase_trade_lot
 
 
 logger = logging.getLogger(__name__)
@@ -2898,7 +2899,7 @@ class FindVessel(Wizard):
         return action, {}
 
 
-class LotQt(metaclass=PoolMeta):
+class LotQt(purchase_trade_lot.LotQt):
     __name__ = 'lot.qt'
 
     @staticmethod