Furnace Air Cleaner Filter, Filter Type Pleated, Performance Rating MERV 13, Actual Depth 4 1/4 in, Actual Height 19 3/4 in, Actual Width 24 5/8 in, Compatible Manufacturer Model Number HCC20-28, Number of Filters 2, Media Material Synthetic, Filter Layer Type Carbon, Electrostatic, Nominal Depth 4 in, Nominal Height 20 in, Nominal Width 25 in, Filters Down To 0.3 micron, Filters Out Dust, , Smoke, Filter Efficiency 75 Percent, Air Flow @ 300 fpm 1,024 cfm, Frame Material Cardboard