POP Safety Relief Valve Body Material Bronze Inlet Type MNPT Outlet Type FNPT Inlet Size 1 in Outlet Size 1 1/4 in Factory Set Pressure 450 psi Pressure Range 15 to 900 psi Disc Material 316 Stainless Steel Overall Height 9 in Application Air and Gas Compressors and Dryers Pressure Vessels and Pressure Piping System etc Seat Material Metal Spring Material Stainless Steel Temp Range -320 Degrees to 422 Degrees F Test Lever Yes Standards ASME Section VIII UV CSA CRN NB