Air Filters

Pleated and fiberglass HVAC filters from AAF Flanders and BestAir in 1, 2, 4 and 5 in. depths, in MERV 1 through 13. Get the depth right first — a 4 in. or 5 in. media filter will not go in a 1 in. rack, and the nominal size printed on a filter runs about half an inch under the actual dimension, which is deliberate and is how they slide in. MERV is a tradeoff, not a ranking: higher MERV catches finer particles but restricts airflow, and a residential blower pushed past MERV 11 to 13 can lose enough flow to hurt the system. Fiberglass panels at MERV 1 to 4 protect the equipment and little else; MERV 8 pleated is the general-purpose choice for a building with normal occupancy.

Looking for a specific size? See the air filter size chart: every size we stock, with MERV or MPR as listed.

Flanders by line: Flanders EZ Flow and PREpleat filters.

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