Series 3000SS Double Check Detector Assemblies prevent the backflow of fire protection system substances from being pumped or siphoned into the potable water supply. It consists of a compact construction and short lay length, ideal for retrofit installations. It features a lightweight stainless steel body, thermoplastic and stainless steel check valves, and low head loss. Series 3000SS can be installed in the horizontal or vertical "flow-up" positions. It is designed for installation on applications identified by local authorities as non-health hazard, such as on fire protection systems. Maximum Working Pressure: 175psi (12.06 bar).