Watts 957 OSY GXG FS 4 Part of the 957 Series Pipe Connection Fitting Z551 4NL P Z551 4NL P Specifications Actuation Yes Assembled Dry No Balance Stop Plate No Ball Material 316 Stainless Steel Body Finish Bronze Body Material Bronze Brand Watts Buy American Act Compliant NO Class Rating Does Not Apply To Product Control Type Electric Actuators CV Rating 73 GPM EAN 098268021028 Electrical Rating 115 V Inlet Connection Size 1 1 2 IN Inlet Connection Size Metric 40 MM Inlet Connection Type Female Threaded Inlet Thread Type NPTF Lead Free YES Maximum Temperature Fahrenheit 150 Minimum Temperature Celsius 40 bottom mounted differential pressure relief valve It has OSY groove by groove gate valves that show if the valve is open or closed and prevent stem corrosion