This 4 in lead-free reduced pressure zone Backflow Preventer assembly prevents the reverse flow of polluted water from entering into the potable water supply due to backsiphonage and or backpressure. It is ideal for protection in continuous pressure piping applications and cross-connections identified as health hazards and from other contaminants found at the service line entrance. This assembly consists of an epoxy coated cast iron body, outside stem and yoke resilient seated gate valves, captured spring check valves, replaceable seats, top mounted test cocks and a field reversible pressure differential relief valve. The coating on this backflow assembly uses ArmorTek technology to resist corrosion due to microbial induced corrosion (MIC) or exposed metal substrate. This backflow assembly contains an integrated 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 relays a signal that triggers notification of potential flooding to service personnel. The add-on sensor connection kit is available for building management systems and cellular communication.