ULTIMATE TOOL AGAINST WILDFIRE SEASON: 2x more activated carbon removes 99.99% of wildfire smoke along with extra protection against other wildfire emissions such as toxic gasses, smog and odors COMPATIBLE WITH BLUE PURE 311i+ Max: Blueair 311i+ Max SmokeBlock Replacement Filter compatible with Blue Pure 311i+ Max Air Purifier FILTERS BUILT TO LAST: Using a 360-degree air intake and up to 4x the filter surface area the Genuine Blue Pure 311i+ Max SmokeBlock Filter lasts on average 6 months; optimizing air flow and performance over time REMOVES EVEN TINIEST AIRBORNE PARTICLES DOWN TO 0.1 MICRON: Particle filter removes airborne particles such as pollen, pet dander, bacteria, mold, viruses, and dust from your indoor environment TRAPS HOUSEHOLD ODORS: In addition to wildfire emissions, active carbon mesh also traps household odors, smoke, chemicals, and volatile organic compounds (VOC) AUTOMATED FILTER REPLACEMENT: Subscribe & save up to 10% on auto-delivered filters when replacement is needed; We recommend replacing your filter about every 6 months when used 24 hours a day BLUEAIR AIR PURIFIERS ARE INDEPENDENTLY TESTED FOR PERFORMANCE & SAFETY, ZERO OZONE: AHAM Verifide for CADR; Ozone Safety Standards Certified by CARB; Trusted Education Partner of British Health Professional Academy