Aprilaire Replacement Drain Spud for use with: Model 550, 560 Humidifiers, 1/2 inch OD Drain, Plastic, Black, 1-1/8 inch height x 1-3/8 inch W
The Aprilaire 4223 Drain Spud is the plastic fitting that attaches to the base of the housing of your humidifier. It is designed to connect to a 1/2 inch O.D. drain hose.
