diff --git a/product.py b/product.py
index e2d7086..37152ff 100644
--- a/product.py
+++ b/product.py
@@ -37,3 +37,35 @@ class Product(metaclass=PoolMeta):
     health_register = fields.Char(
         "Serial", size=None, required=True)
     refurbish = fields.Boolean('Refurbish')
+
+    @staticmethod
+    def default_machine():
+        return False
+
+    @staticmethod
+    def default_risk():
+        return None
+
+    @staticmethod
+    def default_use():
+        return None
+
+    @staticmethod
+    def default_biomedical_class():
+        return None
+
+    @staticmethod
+    def default_main_tecnology():
+        return None
+
+    @staticmethod
+    def default_calibration():
+        return False
+
+    @staticmethod
+    def default_refurbish():
+        return False
+        
+    
+    
+