Hoover Type A Allergen Bag - 9 Bags 4010100A 9 Bags [3 sealed packs, each pk has 3 total 9] Type A Allergen filtration, Designed for high filtration of common household allergens Filters a wide range of airborne particles including many pollens, cat dander, spores and other allergens, Ideal for many with allergic or dust related discomforts Traps 100% of dust mites and their eggs, Traps 99.98% of ragweed and common grass pollens Electrostatically charged liner enhances the capture of extremely fine particles