Bissell Air400 Replacement HEPA Filter - 2 True HEPA + 1 Carbon + 8 Pre-Filters - Compatible with Part# 2521, 2520, 3365 - Ideal for Allergy Relief & Air Purification in Bedrooms, Living Rooms & Offices

【Designed for Air400】Our premium Air400 filters Combo Compatible with Bissell Air400 Purifier, Compared to part# 2521, 2520, 3365.

【3 Stages of filtration】3-Stage Air400 filter features a Pre-Filter, H13 True HEPA Filter, Activated Carbon Filter, the filter targets all common air pollutants such as pollen, pet dander, VOC's, smoke, and odors.

【Filtration Performance】HEPA H13 Meltblown Non-woven air filter media is created using melt-blown technology. It can use mechanical or charged filtration mechanisms to capture 99.97% indoor particles as small as 0.3 microns.

【One Year Combo Pack】It includes 2 HEPA filters, 1 Activated Carbon filters, and 8 Pre-Filters.

【When To Replace Your Filter】Air 400 HEPA filters should be replaced every 6 months, depending on the air quality and environmental factors in your area, Pre-filters should be replaced more often since they help capture larger particles and extend the life of the HEPA filter. We suggest changing the pre-filters every 2-3 months, replace your activated carbon air filter once every 12 months.