Series LF7R Lead Free* Dual Check Valves prevent the reverse flow of polluted water from entering into the drinking water supply at the service entrance or at individual outlets. It consists of a Lead Free* cast copper silicon alloy body construction, with two compact replaceable plastic check modules, and stainless steel springs. Series LF7R is designed for non-health hazard residential water system containment, continuous pressure applications. It is installed immediately downstream of the residential water meter, in a vertical or horizontal position. Check with local inspection authorities for installation requirements. Minimum Working Pressure: 10psi (69 kpa) Maximum Working Pressure: 175psi (12 bar).