The Filtrete Allergen Reduction Filter is designed for housing units accommodating 4 inch nominal size filters. It attracts and captures particles like pollen, mold spores, and dust mite debris.Filtrete 20 x 20 x 4 MPR 1500 Air Filter, made by 3M, helps capture unwanted particles from your household air to contribute to a cleaner, fresher home environment. Designed with exclusive Filtrete 3-in-1 technology, including a high MPR 1500 and MERV 12 rating, your AC filter will help pull and capture countless microparticles – such as pet dander, smoke, bacteria and up to 54% of virus airborne particles (1) – while letting cleaner air flow through. Your Filtrete Filter will also capture large particles, including lint, pollen and household dust. This filter is also CERTIFIED asthma and allergy-friendly (2). Use a 3-month pleated 4-inch home HVAC filter in your furnace, air conditioner or HVAC system. For optimal performance of your heating and cooling system or HVAC system, change your furnace filter at least every 90 days. Note: For easy replacement reminders, create a change countdown in the Filtrete Smart App. Simply use the app to scan the barcode on your filter’s packaging, then choose 30, 60 or 90 days for your replacement countdown. When the filter’s life is up, you’ll get a notification to change your filter. The No. 1 Recommended HVAC Air Filter Brand (3), Filtrete’s Home Air Filters provide the breakthrough technology needed to change how we clean our air, by filtering out particles both large and invisible, to create a cleaner, healthier home for ourselves and our families. (1) Based on airborne MS2 virus testing. Initial efficiency. (2) As outlined in report ASCR: 1246-01. (3) Based on the 2022 Ipsos US Brand Health Study of Residential HVAC Air Filters.