12x20x1 Pure Green Plus Carbon Eco-Friendly AC Furnace Air Filters 6 PackPure Green Plus Carbon Eco Friendly AC Furnace Air Filters by Nordic Pure starts with an environmentally responsible non woven, high loft, antimicrobial filter media made of fine gauge polyester. As we continue to keep our eyes on media technology advances, our Pure Green media will be changing its appearance. Please expect the same quality and performance you have come to rely on from our Pure Green media which will now be white in color on the