Watts 909RPDA Reduced Pressure Detector Assemblies prevent the reverse flow of fire protection system substances from being pumped or siphoned into the potable water supply. The 909RPDA incorporates a meter to detect ground leaks and unauthorized illegal taps, greatly reducing annual water expenses. It consists of an epoxy-coated cast iron body with stainless steel trim, bronze gate valves, a pressure-differential relief valve, shutoff valves, and bronze ball-type test cocks. Series 909RPDA provides maximum flow at low pressure drop utilizing the patented "air-in/water-out" design principle for protection during emergency combined backsiphonage and backpressure conditions. Maximum Working Pressure: 175psi (12.06 bar).