GENUINE BLUEAIR 3210 AND 411 REPLACEMENT FILTER: Created by Blueair and specifically designed to be compatible with the 3210 air purifier to guarantee optimal performance and maximum filtration efficiency; also compatible with 411 and Joy S air purifiers SUPERIOR QUALITY HEPASILENT FILTER: The combination particle and carbon filter removes 99.97% of airborne particles, down to 0.1 microns in size with HEPASilent filtration; HEPASilent technology is unique to Blueair and not available in alternatives EFFECTIVE 2-STAGE FILTRATION: The particle filter traps airborne particles including pollen, dust, mould, pet dander, viruses, bacteria; Activated coconut carbon absorbs light gases, including VOCs, chemicals, and odours from pets, smoke, and cooking NATURALLY ANTIBACTERIAL: The naturally antibacterial polypropylene fibres in Blueair filters prevent bacteria and mould growth, so our filters never put bacteria and mould back into the air UP TO 6-MONTH FILTER LIFE: To maintain optimum performance, we recommend changing your filter once every 6 months when used 24 hours a day; Blueair filters keep your air purifier in the best working condition; alternatives cannot be assured for quality, Weight: 0.5070632026 pounds, Manufacturer: BLUEAIR