US Home Filter SC40-24X24X4 24x24x4 Merv 8 Pleated Air Filter (3-Pack), 24" x 24" x 4",Midwest Supply Inc,SC40-24X24X4" /> Actual size: 23-3/8 inch x 23-3/8 inch x 3-5/8 inch Merv 8 tested under ashrae 52.2-2007 standards Ideal for normal air filtration and those with mild allergies Moisture resistant, heavy-duty Frame Galvanized expanded metal backing