Honeywell Premium Odor-Reducing Air Purifier Replacement Pre-Filter Replacement Filter Type A Plus, including zeolite for extra odor reduction performance Helps reduce odors and maximize HEPA filter life Recommended replacement period: every 3 months Contains 1 filter that can be cut to size to fit Honeywell True HEPA Air Purifier models To ensure stated product performance, use only Genuine Honeywell Replacement Filters.