Series NLF-9 Dual Check Vacuum Breakers for Laboratory Faucets prevent the reverse flow of polluted water from entering into the potable water supply. It consists of a brass body construction with chrome plating, dual check valves, stainless steel working parts, and durable rubber diaphragm and discs. Series NLF-9 is designed for health hazard, non-continuous pressure applications. It is specifically designed for laboratory faucets where portable hoses can be attached. Maximum Working Pressure: 150psi (10.34 bar)