CMP Above Ground Bond Connection [1 1 2" MPT x 1 1 2" Hose] (25810 850 000) h2flow The Val Pak 1 1 2 inch slip The Val Pak 1 1 2 inch slip spring return line check valve is designed for compatible plumbing systems that use slip connections and need dependable one way flow control on the return line Helps support helping route flue gases into an approved vent system when the heater is installed indoors This CMP replacement is especially practical when the original above ground bond connection has worn out or needs a direct compatible renewal with the same threaded and hose format this CMP bond connection is a practical replacement when the original 1 1 2 inch MPT x 1 1 2 inch hose fitting needs renewal