Replacement filter pack compatible with Bissell 2521 HEPA filter and Bissell 2520 carbon filter. Engineered to fit Bissell air400 air purifier， series 24791. Pre-filter acts as first layer of filtration to capture larger particles before reaching HEPA filter. Also removes harmful VOCs and household odors from cooking， cleaning， smoking and pets. True HEPA filter captures up to 99.97 percent of airborne particles as small as 0.3 microns in size including smoke， dust， pollen， pet hair and dander， mold spores and dust mites. Activated carbon filter removes harmful VOCs from the air. Reduces household odors from cooking， cleaning， smoking and pets. Recommended to replace filters every 6 months for maximum efficiency， or more often depending on air quality and environmental factors. Package contains (1) HEPA filter with attached pre-filter and (1) carbon filter.

Replacement compatible with Bissell 2521 HEPA filter and 2520 carbon filter， engineered to fit Bissell air400 air purifier， series 24791

Pre-filter acts as first layer of filtration to capture larger particles before reaching HEPA filter， also removes harmful VOCs and household odors from cooking， cleaning， smoking and pets

True HEPA filter captures up to 99.97 percent of airborne particles as small as 0.3 microns in size including smoke， dust， pollen， pet hair and dander， mold spores and dust mites

Activated carbon removes harmful VOCs from the air， reduces household odors from cooking， cleaning， smoking and pets

Recommended to replace every 6 months for maximum efficiency， or more often depending on air quality and environmental factors， package contains (1) HEPA filter， (1) attached pre-filter and (1) carbon filter， HEPA dimensions: 15.75 in. x 13.38 in. x 1.38 in. carbon dimensions: 15.75 in. x 13.38 in. x 0.98 in.