D4477 Safety Relief Valve Body Material Bronze Inlet Type MNPT Outlet Type FNPT Inlet Size 3/4 in Outlet Size 1 in Factory Set Pressure 150 psi Disc Material B21 Alloy 485 Overall Height 7 1/2 in Application Pressure Reducing Stations etc Steam Boiler and Generators Overall Length 3 1/2 in Seat Material EPR Spring Material Stainless Steel Temp Range -60 Degrees to 406 Degrees F Test Lever Yes Standards ASME Section 1 ASTM A-313 TY 631 National Board Certified Steam