Quick view Compare Add to Cart 20x25x4 MERV 10 AC Furnace 4 Inch Air Filters. 2 Pack. Actual Size: 19-1/2 x 24-1/2 x 3-3/4 $41.98 $36.00 Fast Free Shipping on 20 x 25 x 4 MERV 10 AC & Furnace 4 Inch Air Filters. Actual Size: 19-1/2 x 24-1/2 x 3-3/4. Filtration Rating: MERV 10, MPR 600-700, FPR 5-6. Protects: Lint, Dust, Pet Dander,...