1 inch
10x20x1, 11 1/2 x 11 1/2 x 1, 12x12x1, 12x18x1, 12x20x1, 12x24x1, 14x20x1, 14x24x1, 14x25x1, 14x30x1, 15x20x1, 16x16x1, 16x20x1, 16x24x1, 16x25x1, 18x18x1, 18x20x1, 18x24x1, 18x25x1, 20x20x1, 20x24x1, 20x25x1, 20x30x1, 24x24x1, 24x30x1, 25x25x1
2 inch
10x20x2, 12x20x2, 12x24x2, 14x20x2, 14x24x2, 14x25x2, 15x20x2, 16x16x2, 16x20x2, 16x24x2, 16x25x2, 18x18x2, 18x20x2, 18x24x2, 18x25x2, 20x20x2, 20x24x2, 20x25x2, 20x30x2, 24x24x2, 24x30x2, 25x25x2
4 inch*
12x24x4, 16x20x4, 16x24x4, 18x24x4, 20x20x4, 20x24x4, 20x25x4, 24x24x4
5 inch Honeywell Replacement Media*
16x25x5, 20x20x5, 20x25x5
Generally change filters every 2 - 3 months. During periods where you are using your HVAC system continuously, we recommend you change filters monthly to maintain the best indoor air quality.