GeneralAire 11-GA100A29 - 16" x 25" x 5" Replacement Filter for Honeywell FC100A1029, MERV 11, GFI # 4366

Nominal Filter Dimensions: 16x25x5

Actual Filter Dimensions: 15-7/8" x 24-7/8" x 4-3/8"

Replace the filter every 6 months, depending on the environment may need to be replaced more often.