This 1 1/2 inch reduced pressure zone backflow preventer assembly prevents the reverse flow of high hazard (toxic) fluids found in the water from entering into the potable water supply due to backsiphonage and or backpressure. It is used in water services to industrial plants, hospitals, morgues, mortuaries, and chemical plants and it is also used in irrigation systems, boiler feed, water lines and other installations requiring maximum protection. This assembly consists of a bronze body, threaded quarter turn ball valves, top mounted test cocks, spring loaded check valves, and a pressure differential relief valve. This backflow assembly contains a flood sensor with SentryPlus Alert® technology to detect excessive water discharges from the relief valve. When activated through an add-on sensor connection kit, the flood sensor can send an alert to notify personnel about potential flooding. Add-on sensor connection kits are available for BMS and cellular communications.