Milton S-1091-1 1/2" MNPT Compressor Tank Check Valve 1/2" male national pipe thread 1/8" female national pipe thread side port Maximum working pressure of 450 pounds per square inch Maximum temperature of 400 degrees Fahrenheit Made in USA Milton is your number 1 source for Quality Air Accessories Since 1943 Milton has been producing Quality Air Accessories Milton covers automotive, industrial, hardware, agriculture, heavy-duty fleet and MRO markets