Adjustable Back Pressure Relief Valve Body Material Cast Iron Inlet Type FNPT Outlet Type FNPT Inlet Size 1/2 in Outlet Size 1/2 in Factory Set Pressure 28 psi Disc Material Stainless Steel Overall Height 6 3/4 in Overall Length 4 3/4 in Seat Material Monel Spring Material Stainless Steel Temp Range 40 Degrees to 450 Degrees F Test Lever No Standards CRN CSA