This 4" double check detector backflow preventer assembly prevents the backflow of fire protection system substances from being pumped or siphoned into the potable water supply. It is designed for installation on applications identified by local authorities as non-health hazard, such as on fire protection systems. This assembly consists of a compact construction and short lay length, ideal for retrofit installations and can be installed in a horizontal or vertical flow-up position. It features a lightweight stainless steel body, thermoplastic and stainless steel check valves that provide low head loss. It has a gallons per minute meter, outside stem and yoke shutoffs, and tamper switch. The maximum working pressure is 175 psi (12.06 bar).

• Includes UL-listed fire tamper supervisory switch
• Stainless steel for corrosion resistance
• Designed for minimum head loss
• 150 pound ANSI/AWWA CL D flanged
• Outside stem and yoke shutoffs