The #35 Aprilaire Comparable Humidifier Replacement Water Panel (2-Pack) by Tier1 is the heart of your humidifier, designed specifically to deliver the proper humidity to your home during the heating season. This product removes pollutants from the water used by your humidifier, producing cleaner water and better indoor air quality. It is recommended that you replace this water panel every 6 months for best results. Additionally, the water panels are made of aluminum and can be recycled. The #35 Aprilaire Comparable Humidifier Replacement Water Panel 2-Pack by Tier1 fits Aprilaire 560, 600, 700, 760, 350 and 360 humidifier models. Order today!