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EPA tests: Do-it-yourself air filter removes 99% of viruses
Pentek 455903-43, FloPlus-10 Carbon Filter, 2.5" x 10" | Serv-A-Pure
Amazon.com: Greentech Environmental Active HEPA+ PRO Replacement Filter with ODOGard Coating - HEPA Filter Replacement Works with Active HEPA+ Room Air Purifier, 1 Pack : Home & Kitchen