HSH-Flo 1/4" Electric Solenoid Valve, AC110V NPT Normally Closed Electrical Valve Water Air Oil Suitable For Gas, Water, Diesel Normally Closed When Power Off Medium Temperature From 23 Fahrenheit To 248 Fahrenheit; Inlet/Outlet Ports1/4" Female NPT Threads (18 threads per inch / US Standard) EPDM Sealing Material ,Both wires can be used as positive or negative