Arm & Hammer Odor Eliminating Vacuum Filter, Eureka HF-7: * Baking soda particles neutralize odor-bearing chemicals * Releases clean, odor-free air into your home as you vacuum * Replace filter every 90-120 days for optimal performance * For use in Eureka 2270 Series; Contour Maxima and Powerline (2900-2920 Series); EZ Kleen, SurfaceMax, 200 and 300 (2940, 2960, 2970 Series) and Select Whirlwind, Whirlwind Plus, Pet Lover, Pet Expert and Clean Living (3270, 3280 Series) Uprights