The Pratt PSI Surge Inhibitor check valve from Henry Pratt Company uses a reinforced flexible disc made from a stainless steel hinge pin with nylon reinforcement in the hinge and an alloy steel disc plate fully encapsulated in a specially formulated rubber compound that resists wear. The hinge tab of the disc is secured between the valve body and disc. The disc is able to pivot about the reinforced hinge section. It helps reduce or eliminate valve slam. A stainless steel flexor assembly affixed to the disc increases the speed of closure by stiffening the hinge section of the disc. The valve is field adjustable without removing from the line. It is manufactured to comply with AWWA C508 and is NSF/ANSI 61/372 certified. 877/436-7977; www.henrypratt.com.