This 8 inch lead free testable reduced pressure detector backflow preventer assembly prevents the reverse flow of fire protection system substances from being pumped or siphoned into the potable water supply. It incorporates a meter to detect ground leaks and unauthorized illegal taps, greatly reducing annual water expenses. It consists of a compact, stainless steel body with stainless steel internal parts, two check valves, a pressure-differential relief valve, shutoff valves, torsion spring checks and relief valve, and bronze nickel plated test cocks. It is 70 percent lighter than traditional designs and is ideal for health hazard cross-connection, such as on fire sprinkler systems. Maximum working pressure is 175 psi (12.06 bar).