US Home Filter SC60-12X24X4 MERV 11 Pleated Air Filter (3 Pack), 12" x 24" x 4" Actual size: 11-3/8" x 23-3/8" x 3-5/8" Merv 11 tested under ashram 52.2-2007 standards Ideal for those with moderate allergies Moisture resistant, heavy-duty frame Galvanized expanded metal backing