Looking for an air filter that can do it all? Look no further than the Filtrete 16x25x1 Air Filter MPR 1000 MERV 11, Allergen Defense, 4-Pack. This filter uses electrostatically chargedfilter media to trap 99.97% of airborne particles as small as 0.3 microns*. That means that pollen, pet dander, smoke, bacteria and viruses are all no match for this powerful filter. In addition to its top-notch filtration capabilities, the Filtrete 16x25x1 Air Filter MPR 1000 MERV 11, Allergen Defense, 4-Pack also features a durable design that can withstand up to 90 days of use. So, you can rest assured that your air will be fresh and clean for the long haul. Whether you have allergies, pets or are just looking for peace of mind, the Filtrete 16x25x1 Air Filter MPR 1000 MERV 11, Allergen Defense, 4-Pack is the perfect choice. *Based on ASTM D4956-09