New Case of 12 14x20x1 Air Conditioner Furnace Filter Hvac Filters Usa Sale FURNACE HVAC FILTERS 14' X 20' X 1' BRAND NEW IN BOX!! SUPER SALE PRICE!! utilizing the Purolator Monobond concept of a one-piece frame sealed to the media using heat and pressure. Fiberglass media is evenly coated with a gel adhesive to prevent finer particle migration. Full depth loading and high dust holding capacity. Filter media has a skin backing and is evenly coated with a gelled adhesive. FIBERGLASS Size Ins.=14 x 20 x 1