Nordic Pure 20x25x4/20x25x5 (19 7/8 x 24 7/8 x 4 3/8) Honeywell FC100A1037 Replacement Pleated AC Furnace Air Filters MERV 12, Box of 1 Superior Air Filter for Residential or Commercial Property Comparable to a MPR rating of 1500-1996 Hypoallergenic and antimicrobial pleated electrostatic filter material