US Home Filter SC40-24X24X1-6 24x24x1 Merv 8 Pleated Air Filter (6-Pack), 24" x 24" x 1" Actual size: 23-3/8 inch x 23-3/8 inch x 3/4 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