Engel Locking Hasp. A stainless steel hasp that allows your MHD13F-DM fridge-freezer to be securely double locked with an additional pad lock. They do not interfere with the performance of your Engel - if installed properly. Locking hasp's are only sold to be installed by Engel technical staff. We don't recommend that customers install the hasp as there is a very real risk of puncturing a gas line.