AQUATROL 740EF-M1A-175 Safety Relief Valve, 1 x 1-1/4, 175 psi. More details: Safety Relief Valve, Body Material Brass/Bronze, Inlet Type MNPT, Outlet Type FNPT, Inlet Size 1 In., Outlet Size 1-1/4 In., Factory Set Pressure 175 psi, Disc Material Stainless Steel, Overall Height 8-1/8 In., Application Air, Gas, Overall Length 8-1/8 In., Seat Material Brass/Stainless Steel, Spring Material Stainless Steel, Temp. Range -320 Degrees to 406 Degrees F, Test Lever Yes, Standards ASME Section VIII / CRN.