These Hoover Type S Bags fit Hoover Futura, Spectrum and Wind Tunnel Canister vacuums. Each package includes 9 bags, which feature 99.7% filtration of dust and allergens, as well as capture microscopic particles, germs, and bacteria as small as 0.1 microns. For optimum performance, it is suggested to change your bag every 1-2 months! By retaining dust, pollen and other particulates and allergens from the air while you vacuum, these vacuum bags make the air in your home or business cleaner and more breathable. Purchase a pack for your vacuum cleaner today!