Sprinkler valve, 2 ½" F. NPT inlet x 2 ½" F. NPT outlet. Used to regulate and control high pressures in standpipe and sprinkler systems. Constant pressure regulation under residual (flowing) and static (non-flowing) conditions. Tamper-proof pressure setting. Valve seat acts as checking device and closes when inlet pressures drop below selected static outlet pressures. Optional monitor switch adapter bracket permits valve supervision by electrical means. In-line (straight) type, cast brass body with brass and stainless steel internals. UL listed to 400 psi.