Choose these Filtrete maximum allergen reduction air filters and say goodbye to polluted air in your home! This model is designed to capture particles to contribute to a cleaner, fresher air. Because the quality of the air you breathe at home is so important, it features a high MPR rating of 1900. It's therefore very effective against microparticles such as pollen, smoke, bacteria, viruses, and pet dander. It can even get rid of cough and sneeze debris, as well as large particles, including lint, pollen, and household dust. It does so by capture from the air passing through it. For optimal performance, filters should be changed every 90 days.