This 211i Max replacement filter fully compatible with Blueair Blue Pure 211i Max Air Purifier, replace part F2MAX Filter Excellent Filtration: The 211i Max filter captures up to 99.97% of airborne particles as small as 0.1 micron in the air passing through the filter, the activated carbon filter clean light household odors from smoking, pets, and cooking odors This Filter ONLY compatible with 211i Max Air Purifier, Not compatible with 211+ or 211+ Auto, 411i max, 411ia, 511, 311, 121, or other models, please note Easy installation of 211 i max replacement filter. We recommend that you change your blueair replacement filter every 6-12 months for optimal performance of your machine, it's easy to install We are committed to customer satisfaction. Save money with XBGG filter for blueair replacement filter! XBGG 2 Pack 211i Max Replacement Filter Compatible with Blueair Blue Pure 211i Max, F2MAX Replacement Filter for 211i Max Air Purifier, 2-in-1 HEPA with Activated Carbon Filter, Compared part #F2MAX. XBGG 2 Pack 211i Max Replacement Filter Compatible with Blue Pure 211i Max Air Purifier, H13 211iMax Replacement Filter, Compared Part F2MAX