Hayward Check Valve, 4 in, Single, Inline True Union, PVC, FNPT x FNPT TC1400TE Toilet Partition Panel The door to the dispenser The door to the dispenser closes with a stainless steel piano hinge and is outfitted with a standard Bobrick keyed tumbler lock to prevent theft of the towels inside The dispenser is made from Type 304 heavy gauge stainless steel with a satin finish to reflect light while showing less fingerprints and smudges and are suitable for cleaning aggressive chemical spills The true union design eases valve removal from piping systems without having to break down the pipe connections Designed to help prevent the reversal of flow in piping systems where backflow could cause damage to filters