Honeywell UV True HEPA 5-1 Allergen Remover Tower UV Technology helps reduce airborne bacteria, virus's, fungus and mold spores Enhanced odor absorbing pre-filter reduces unpleasant household odors faster Advanced electronic controls, 12 cleaning levels, 1-18 hour timer, filter clean indicator and oscillation Replacement Filter 2 pack: HRF-N2 Replacement odor reducing pre-filter: HRF-B1, or HRF-B2