Our Accumulair 21x21x4 air filter is solely engineered to be compatible with same sized 21x21x4 air filter type. Pleated electrostatically charged filter media traps airborne contaminants according to the MERV standard rating. Free of chemicals. Note: The example filter picture displayed is not to scale and is shown for style only. Catalog and 21x21x4 air filter variations are up to date as of 03/24/2020.
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- 30-day 100% return policy.
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