Amazon.com The Filtrete 1900 MPR Ultimate allergen reduction filter not only vastly improves the air quality in your home, it also keeps your air conditioning and heating systems running efficiently, saving on utilities and maintenance costs. The electrostatic filter attracts and captures airborne dust, pollen, dust-mite debris, lint, mold spores, pet dander, smoke, smog, bacteria, particles that can carry viruses, and particles that can carry odors. With each pass through the specially pleated filter, the air in your living space improves, making for a healthier home environment. This high-performance filter outperforms comparable non-electrostatic fiberglass and washable and reusable one-inch filters. Electrostatic Design Captures More Particles The 3M Ultimate allergen reduction filter is made with both positively charged and negatively charged fibers that act like tiny magnets to attract air-polluting contaminants. Since particles in the air are either positively or negatively charged, they are attracted to and captured by the filter and kept out of your living space. Electrostatic filters, including the 3M Ultimate allergen reduction filter, perform better than comparable non-electrostatic fiberglass and washable/reusable filters, because they attract and capture the small, allergy-aggravating microparticles that non-electrostatic filters can't. Improves Indoor Air Quality With indoor air a surprising two to five times more polluted than outdoor air, the 3M Ultimate allergen reduction filter can make a difference in maintaining a healthier home environment by cleaning air with each pass through the filter. The 3M Ultimate allergen reduction filter features a 1900 Microparticle Performance Rating (MPR), which means it is able to capture large and small particles from the air, including household dust, pollen, dust-mite debris, mold spores, pet dander, smoke, smog, bacteria, particles that can carry viruses, and particles that can carry odors. This high-performance filter meets American Lung Association of the Upper Midwest Health House Program’s indoor air quality guidelines. Improves Efficiency This high-performance allergen-reduction filter also keeps your heating and air conditioning equipment working efficiently by removing dirt and reducing strain on the motor. It is recommended that you change the filter every three months. However, the effectiveness and life of the filter can vary and depend on the individual conditions in your home. About Filtrete Air Filters For nearly 25 years, Filtrete filters have delivered cleaner air to millions of homes, becoming a leader in residential air filtration. Developed by 3M engineers to help capture airborne allergens, the Filtrete filter media is electrostatically charged to act like tiny magnets to attract and capture microscopic particles from the air as it passes through the filter. Today, a dedicated technical team continues to develop innovative filtration solutions for around the home, including air cleaning filters, room air purifiers, and water filtration products. What's in the Box Pack of six 3M 1900 MPR Ultimate allergen reduction filters. Product Description Your home should be your sanctuary, starting with the air you breathe. Filtrete Premium Allergen, Bacteria & Virus Air Filters help capture unwanted particles from your household air, contributing to a cleaner, fresher home environment. By proactively capturing dust, bacteria, viruses and allergens, these high performance filters help improve your home’s air quality.