diff --git a/sqlalchemy_utils/types/password.py b/sqlalchemy_utils/types/password.py
index c2a03d0..c558f74 100644
--- a/sqlalchemy_utils/types/password.py
+++ b/sqlalchemy_utils/types/password.py
@@ -115,6 +115,7 @@ class PasswordType(types.TypeDecorator, ScalarCoercible):
 
     """
 
+    impl = types.VARBINARY(1024)
     python_type = Password
 
     def __init__(self, max_length=None, **kwargs):