The Aprilaire 4040 filter is the genuine Aprilaire solenoid for model 220, 224, 440, 550, 558, 560, 568, 600, 700, 760, 768.

Important features of the Aprilaire 4040 Solenoid Filter:

• Includes the strainer 4004, which is installed in the valve body of the Aprilaire solenoid. 
• Specifications printed on the Aprilaire solenoid body: 24 volts, 60 Hz, orifice 3/32.

Both the inlet and outlet of the Aprilaire 4040 are threaded 7/16"-24 UNS in order to accept a compression fitting for ¼" tubing. The Aprilaire solenoid inlet includes the compression fitting and ferrule. For the outlet, your existing compression fitting is reused.