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 cou