The Conbraco Series 40-200 Reduced Pressure Backflow Preventer is FM and UL Approved and consists of two independently acting, spring-loaded check valves with a differential pressure relief valve located between the check valves. The all bronze relief valve module is easily removed from the ductile iron check valve body. Pressure sensing passages are built into the bronze relief valve module to prevent possible damage from mishandling or vandalism. The unit is available with inlet and outlet shut-off valves. Four test cocks, three on the backflow preventer valve body and one on the inlet shut-off valve, complete the assembly.