The AprilAire A12PR is the correct replacement filter for the following humidifier models:
The Aprilaire 12 Humidifier Water Panel Filter for 440 is a heavy duty metal water pad for select Aprilaire humidifier models. This compatible verision of the genuine Aprilaire 440 humidifier filter is also referred to as the A12PR replacement water panel. This Aprilaire water panel is for use on your Aprilaire, Chippewa, and Walton humidifier systems and filter harmful mineral contaminants and pollutants from indoor air.
Aprilaire 12 Humidifier Water Panel Filter for 440 specifications:
The Aprilaire humidifier filters helps your Aprilaire humidifier system generate humidity and improve environmental conditions in your home. This Aprilair humidifier water panel is also available in paper media as AprilAire #12 Humidifier Water Panel Filter.
Note: AprilAire is also known as April Aire, April Air and Aprilair.