Aerostar 16 1/2 x 21 5/8 x 1 MERV 11 Pleated Air Filter, AC Furnace Air Filter, 6 Pack Nominal Size: 16 1/2 x 21 5/8 x 1, Actual Size: 16 1/2" x 21 1/2" x 3/4" Comparable to 3M Filtrete MPR 1000-1200 Micro Allergen Defense and Honeywell Allergen Plus FPR 7 Filters out microscopic particles and allergens such as lint, dust mites, spores, pollen, pet dander, fine dust, and smoke For best results, change your filters every 60-90 days. Increase frequency to every 30 days during peak summer and winter months Made with electrostatically charged synthetic material for high filtration efficiency with low air flow resistance Manufactured in the USA by Filtration Group, a world-leading manufacturer and supplier of filtration solutions for healthier indoor air quality
