This 1/2 inch pressure relief valve is used in fire protection grid systems to protect against excessive pressure from thermal expansion or line surge. It consists of a bronze body construction with 1/2 inch NPT threaded male inlet and 1/2 inch NPT threaded female (drain) outlet, test lever, and stainless steel spring. This valve is UL listed. The pressure relief is set at 175 psi (1206.6 kPa).