MrSteam 4" x 3" x 5" Brass Pressure Release Valve For MS, MSSUPER, and SAH Residential Generators"MAKING STEAM SINCE 1917" The pressure reducing valve with a balanced piston design has an internal thermal expansion bypass, corrosion resistant sealed bronze body, bonnet, and an integral SS strainer. Pressure Reducing Valve For MS, MSSUPER, and SAH Residential Generators Features Stainless Steel springs Corrosion Resistant Sealed Body and Bonnet Integral SS Strainer Balanced Piston Design Internal Thermal Expansio By Pass Maximum Supply Pressure up