20x25x4 Space Gard Filter Filter, Case of 2

20" x 25" x 4", Space Gard Filter, Electrostatically Charged Media, Fits Aprilaire & SpaceGard Model 1210, 3210, 4200, 2210, & 220/2120, MERV 13, Lasts Up To 1 Year, Effective Against Pollen, Mold, Bacteria, Dust/Lint, Virus Carriers.