Nominal: 16 x 20 x 516x20x5, AC Furnace Air Filter Nominal Size: 16 X 20 X 5, Actual Size: 15 7/8" x 19 3/4" x 4 3/8" Comparable to Filtrete MPR 1500 and 1550 Ultra Allergen Defense Replaces Honeywell Part Numbers: F25, F25F1075, 209894, F35, F35R, F35F1032, FC35A1035, F100, F100F1004, F150, FC100A1003, F200, FC200E1003, F251075, F35F1032, F100F1004 Replaces Lennox Part Number: X0582
