Filtration bags meet all HEPA certifications and specifications. Constructed with three layers of Filtrete HEPA filter media. Fits all Hoover® bagged upright cleaners, including the WindTunnel uprights, that use "Type Y" or "Type Z" bags. OEM/Compatible: OEM; For Use With: Hoover® Commercial CH53005, UH30301; Quantity: 2/Pack.