The Fellowes? AeraMax? DX55 True HEPA Filter captures 99.97% of particles and impurities as small as 0.3 microns, including mold spores, pollen, dust mites, most airborne microbes, allergens and cigarette smoke. Filter is compatible with the Fellowes? AeraMax? DX95 Air Purifier. Replace the True HEPA filter approximately every 12 months to ensure that the Air Purifier continues to operate optimally.