Hoover 40130050 Allergan Cartridge Filter Allergen filtration cartridge filter fits in dirt cup of all Hoover Foldaway models in the 51000 series and Turbo Power 3100 including these popular models U5162906, U5162911, U5164900, U5165900, U5167900, U5167950, U5170900, U5172900, U5173900, U5173950, U5174900, U5175900, U5175950, U5176950, U5177900, U5178900, U5179900, U5179906, UH40155, UH40185, UH40190. Replaces the 43615090 filter. Approximately 5 12 in wide x 2 34 inches tall. Change every 3 to 6 months.