Eco-safe Air Filters (series products) Benefits: 1) The High Filtration Capability Eco-safe Air Filter Sheet had passed ASHRAE STANDARD 52.1-1992 TEST with 95% efficiency, which is as good as the Face-masks that Doctors and Nurses use in the Hospital. It can help people reduce Allergic Symptoms at Home, Office and Hospital. 2) The High Air Flow Filter Sheet can effective against these common Household contaminants. Such as, Pollen, Dust Mite Debris, Mold Spores, Pet Dander, Smoke, Bacteria, Debris & Lint, Household Dust and Protect Heating and A/C. 3) Easy use: Two Way Technology - "Impossible to install wrong". 4) No Waste: 100% paper and plastic can be recycled. Save Environment! 5) Save Money: The re-usable Plastic Frame last 3 - 5 years.