4 Inch Filters

Fortify 20x20x4 MERV 11 Pleated Whole House Air Filter. (2-Pack) Replacement for TopTech TT-FM-2020, White Rodgers FR1600M-108, FR1600M-111 | Actual Size 19.38 x 19.38 x 3.63

Fortify 16x25x4 MERV 11 Pleated Whole House Air Filter. (2-Pack) Replacement for TopTech TT-FM-1625, White Rodgers FR1400M-108, Pro1 IAQ F1608, F1612 | Actual Size 15.38 x 24.38 x 3.63

Fortify 20x25x4 MERV 11 Pleated Whole House Air Filter. (2-Pack) Replacement for TopTech TT-FM-2025, White Rodgers FR2000M-108, Pro1 IAQ F2008, F2012 | Actual Size 19.38 x 24.38 x 3.63

Fortify 16x25x4 MERV 11 Air Cleaner Replacement for Honeywell FC100A1029 Pleated HVAC Filters. (2-Pack) | Actual Size: 15-7/8 x 24-3/4 x 4-3/8

Fortify 20x25x4 MERV 11 Air Cleaner Replacement for Honeywell FC100A1037 Pleated HVAC AC Furnace Filters . (2-Pack) Actual Size: 19.88 x 24.75 x 4.38

Fortify 20x25x4 MERV 11 Air Filters (2-Pack) | Replacement for AprilAire 210 & 213 Media Air Cleaners | Compatible with Models 1210, 1620, 2210, 22216, 32100, 4200, 2120, and with Kit 1213, UV12.

Fortify 16x25x4 MERV 11 Air Filter | Replacement for AprilAire 410 & 413 Media Air Cleaners | Compatible with Models 1410, 1610, 2140, 2400, 2410, 2416, 3410, 4400, and Space-Gard 2400 with Kit 1413

24x24x4 MERV 11 HVAC Air Filters

20x25x4 MERV 11 HVAC Air Filters

20x24x4 MERV 11 HVAC Air Filters

20x20x4 MERV 11 HVAC Air Filters

18x24x4 MERV 11 HVAC Air Filters

16x25x4 MERV 11 HVAC Air Filters

16x20x4 MERV 11 HVAC Air Filters

12x24x4 MERV 11 HVAC Air Filters