Series 7B Dual Check Valves prevent the reverse flow of polluted water from entering the potable water supply at the service entrance or at individual outlets. It consists of a compact brass body construction, two independently operating check valves, and is available with a female union inlet x female union outlet and NPT threaded connections. Series 7B is designed for non-health hazard residential water system containment, continuous pressure applications. Check with local inspection authorities for installation requirements. Maximum Working Pressure: 150psi (10 bar), Maximum recommended flow: 15 gpm (57 lpm).