Turn your central heating and cooling system into a high-efficiency air filtration unit thanks to these elite allergen Filtrete furnace filters from 3M. These fibreglass filters were specially designed with a 2200 Microparticle Performance Rating to ensure you and your family will only be breathing the cleanest air possible. These electrostatic air filters are 5 times more effective than non-electrostatic filters at capturing small particles. They have the ability to attract small and large allergens of all kinds, including viruses, bacteria, mould spores, dust, lint, pollen, dander, smoke, and the list goes on! For best results, don't forget to change your filter every 90 days. This particular model measures 20 inches x 20 inches and is designed for residential use only.