This 2 1/2" lead free reduced pressure zone backflow preventer assembly with SentryPlus Alert technology for flood detection is designed to prevent the reverse flow of contaminated water from being pumped or siphoned into the potable water supply due to backsiphonage and or backpressure in accordance with national plumbing codes and water authority requirements, as well as provide continuous monitoring, multi-channel alerts, and automatic shutoff capability in the event of a possible flood condition. The LF909 Backflow preventer features an exclusive air-in-water-out principle relief valve for increased protection during backflow emergencies. The coating on this backflow assembly uses ArmorTek(R), a patented 3-part advanced epoxy coating system designed to limit both microbial induced (MIC) and exposed metal substrate corrosion. The assembly uses OSY shutoffs. This backflow assembly also includes a backflow flood sensor alert that monitors the condition of your backflow assembly 24/7 and alerts you in the event of RPZ discharge. Simply connect to the SentryPlus Alert System or to your BMS and activate it.