diff --git a/sale.py b/sale.py
index 12255d3..4215237 100644
--- a/sale.py
+++ b/sale.py
@@ -39,6 +39,8 @@ class Sale(metaclass=PoolMeta):
                 del v['id']
             if v.get('amount'):
                 del v['amount']
+            if v.get('unit_price_w_tax'):
+                del v['unit_price_w_tax']
             v['type'] = 'line'
             product = Product(v['product'])
             v['unit'] = product.template.default_uom.id