3M Filtrete 16x25x1 AC Furnace Air Filter MPR 1000 Micro Allergen 2-Pack MERV 11. OUTPERFORMS FIBERGLASS, WASHABLE AND NON-ELECTROSTATIC 3-month pleated 1 in. home air filters for your furnace, air conditioner or HVAC system DESIGNED WITH EXCLUSIVE Filtrete? Brand 3-in-1 technology from 3M to trap unwanted air particles while letting cleaner air flow through ATTRACTS AND CAPTURES particles such as lint, pollen, dust, pet dander, smoke and smog 1000 MPR has a rating of MERV 11 The higher the MPR, the more microparticles--such as pollen, pet dander, smoke, bacteria and viruses--your filter will capture from the air passing through it FIND YOUR SIZE: MPR 1000, MPR 1200 and MPR 1550 available in 4 in., 4 in. slim fit and 5 in. thick air filters FOR OPTIMAL PERFORMANCE of your heating cooling system or HVAC system, change your home air filter at least every 90 days for 1 in. filters, and at least every 12 months for 4 in. and 5 in. filters