The fellowes aeramax dx5 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. Built-in aerasafe antimicrobial treatment protects from the growth of odour causing bacteria, mildew and fungi. Filter is compatible with the fellowes aeramax dx5 air purifier. Replace the true hepa filter approximately every 12 months to ensure that the air purifier continues to operate optimally.