Filtrete 20x30x1 MPR 300 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 an MPR 300 and MERV 5 rating, your AC filter will help pull and capture lint, household dust and dust mite debris, while letting cleaner air flow through. This 20x30x1 air filter outperforms fiberglass, washable and non-electrostatic air filters to help keep your air cleaner. Use a 3-month pleated 1-inch home HVAC filter in your furnace, air conditioner or HVAC system. Six come in a pack, so keep a few filters as backup, or use them in multiple areas. For optimal performance of your heating and cooling system or HVAC system, change your furnace filter at least every 90 days. (1) Based on the 2022 Ipsos US Brand Health Study of Residential HVAC Air Filters.