AprilAire 45 Water Panel Humidifier Filter Replacement for AprilAire Whole-House Humidifier Models 400, 400A, 400M (Pack of 2)

This genuine Aprilaire replacement water panel is the backbone of your Aprilaire humidifier. The heavy-duty paper panel is reinforced with 2 layers of aluminum and coated with an anti-microbial agent to prevent the growth of biologicals. The panel absorbs water and maintains the proper level of hydration to support the evaporation process. Water is vaporized as air warmed by the furnace passes over the water panel. The humidified air is carried through the house through the air ducts.