Return Air Grille Filter is a high efficiency, replacement for return grille applications. Designed to capture airborne particles that circulate through the filter. Nominal Dimension 16x25x4. Genuine Honeywell Part.

Specifications:

Nominal Size: 16x25x4
Actual Size: 15 3/4" x 24 3/4" x 4 3/8"
Captures Particles down to .3 microns in size
High-Efficiency alternative to one-inch filters
MERV 10 Rating
1" Lip
The FC40R features a special design that allows it to fit in the same space as a standard 1" return grille filter, while offering filtration up to forty times more effective (versus 1" fiberglass filters). This filter will clean your air down to 0.3 microns, trap dust, pet dander, pollen, mold, bacteria and other allergens.

replaces older model number F35R Series Filters and provide a high-efficiency alternative to 1 inch filters. This filter should be replaced at least once per year for maximum efficiency. Filter life based on air quality.

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Air Grille