Watts LF909 Lead Free Reduced Pressure Zone Assemblies prevent the reverse flow of polluted water from entering into the potable water supply due to backsiphonage and or backpressure. It consists of a bronze body construction, bronze ball valve shutoffs, and bronze test cocks. Watts 909 features a patented "air-in/water-out" design principle for protection during emergency combined backsiphonage and backpressure conditions. It is ideal for health hazard cross-connections or for containment at the service line entrance. Check with local water authorities for installation requirements. Maximum Working Pressure: 175psi (12.06 bar).