Safety Relief Valve, Body Material Brass, Inlet Type MNPT, Outlet Type FNPT, Inlet Size 3/4 in, Outlet Size 3/4 in, Factory Set Pressure 30 psi, 510,000 BtuH, Disc Material Silicone, Overall Height 3 11/32 in, Application Hot Water Space Heating Boilers, Water Supply Heaters and Storage Tanks., Overall Length 3 11/32 in, Seat Material Silicone, Spring Material Stainless Steel, Temp. Range 0 Degrees to 250 Degrees F, Test Lever Yes, Compliance ASME Section IV, Standards ASME Section 1V