The Filtrete Micro Allergen Furnace Filter is for people who want to help reduce allergens and microscopic particles from the air in their homes. The Filtrete Micro Allergen Furnace Filter captures large airborne allergens like household dust, pollen and mold spores. * Allergy-reducing 3M filter * MERV Rating:11 * MPR: 1000 * Electrostatically charged fibers * Meets American Lung Association guidelines * Easy to replace every 3 months * Sold as 6 Pack