Graco Back Pressure Regulator, Low Pressure Corrosion Resistant, 180 Max psi, SST, Manual, 1-1/4 (f) x 1-1/4 (f), with GaugeFEATURES Control upstream fluid pressure with Graco back pressure regulators. Our back pressure regulators use closed loop control to maintain the pressure of the system regardless of flow demand. This allows operators to trigger guns, valves, and other flow controls without changing the system pressure. Stainless steel wetted materials are compatible with catalyst and waterborne materials Hardened stainless steel seat ensure low wear and long life