No longer available. Use the Aprilaire 4040 or the Skuttle A01-0814-148. This solenoid valve mounts on the HE440 water filter housing and is wired to the HE440. The valves inlet side has a 1/8" npt female and the outlet has a compression fitting for 1/4" tubing. The valves orifice is 1/16". The mounting bracket holes are spaced 2-1/8". To test this valve, connect 24 vac to the leads. The solenoid should make a click. Air can be blown through the valve when energized.