There are 2 version: Top inlet connection or Bottom inlet connection

The Chemetron® 400 Series outlet stations provide convenient access to medical gases in patient care locations. They are fully compatible with Chemetron-style latch-keyed adapters. Finish plates are stainless steel with a satin finish. Outlet finish plates and rough-in plates are safety keyed for positive cross-connection prevention. Primary valves are separate from the finish plate, allowing easy testing for leaks and cross-connection.