Aprilaire Water Panel 12 is the heart of your humidifier, designed specifically by Aprilaire for your Aprilaire humidifier; it delivers the proper humidity to your home whenever you heat your home. Replace annually for peak performance.
Approximately 11-1/2" x 14-3/4" x 1-3/4"
Aprilaire: 112, 224, 440, 445A, 445 and 136
Chippewa: 224 and 225
Walton 600, 620, 660
Other Stock Numbers: UAPRILAIRE12O
Aprilaire recommends for peak performance to replace the water pad annually.