Actual dimensions are 20.1 x 21.1 x 5. Accumulair brand 21x21.5x5 Honeywell TRN2121T1 replacement whole house air filters, specifically constructed to replace the OEM Honeywell TRN2121T1 air filters. Fully constructed so no forming or combs required. MERV rated to ASHRAE 52.2 test ratings assuring particle capture as good or better than the OEM Honeywell TRN2121T1 air filter. Notice: Sample filter picture shown is not to scale and is shown for construction only. Name brands and Honeywell TRN2121T1 part numbers shown for filter substitution identification purposes.
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- 30-day 100% return policy.
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