This Honeywell Air Purifier A Pre-Filter helps capture larger airborne particles such as dust, lint, fibers and pet fur, while helping to absorb some common household VOC gases and fumes.* The Honeywell Replacement Pre-Filter A fits Honeywell Air Purifier models: HPA094 series, HPA100 series, HPA101 series, HPA104 series, HPA104 series, HPA105 series, HA106 series and HPA5100 series models. This package contains 4 pre-filters (1-year supply). Replace pre-filter every 3 months for best performance. Always purchase Genuine Honeywell replacement air purifier filters and pre-filters. They are certified to help capture odors and the following microscopic allergens and particles: dust, pollen, pet dander, dust mite debris, and smoke.* Other compatible filter replacements are not guaranteed to offer the same performance or efficiency. Disclaimers: * From the air that passes through the filter, 0.3 microns and larger. ** Based on 3rd party independent CADR testing for the smoke CADR value when operated at the highest level. Air circulation depends on many factors, such as room size and configuration. There is no guarantee that all of the air in a room will pass through the filter.