Fits inside the filter door of WindTunnel Self-Propelled uprights andWindTunnel Bagless uprights with the Allergen Filtration Systemincluding U57009RM, U5720950, U5720960, U5725900, U5725960, U5750906,U5750911, U5752900, U5753900, U5753950, U5753960, U5753980, U5760900,U5760910, U5768900, U5786900, U6471900, U66009RM, U6607900, U6616900,U6617960, U6618900, U6630900, U6632900, U6634900, U6637900, U6637960,UH40020, UH40065, UH40115CA, UH40125, UH60000. Includes 2 filters perpack. Measures 10 7/16" x 3 5/16" x 1/2".