Fits Blue Pure 411 Auto, 411, And 411 Air Purifiers. Blueair Blue Pure 411 The Blue Pure 411 Series SmokeBlock Replacement Filter is the ultimate tool against wildfire season. Additional activated carbon removes 99.9% of wildfire smoke along with extra protection against other wildfire emissions such as toxic gasses, smog and odors while also eliminating harmful gaseous pollutants such as volatile organic compounds (VOCs). In addition, advanced polypropylene filter media removes particle pollutants down to 0.1 micron in size from your indoor air, such as pollen, dust, and pet dander. Using a 360-degree air intake and up to 4 times the filter surface area vs. the same models with only mechanical filtration (H13 filter), the Blue Pure 411 Series SmokeBlock filter lasts longer, on average 6 months. Subscribe save up to 10% on auto-delivered filters when replacement is needed; We recommend replacing your filter about every 6 months depending on usage. ULTIMATE TOOL AGAINST WILDFIRE SEASON: 99.9% wildfire smoke removal based on removal testing of particles 0.4-0.7um in 60min in a 30m3 room. Performance may vary. Also tested on benzene, toluene, nitrogen oxide, sulfur dioxide. FILTERS BUILT TO LAST: Blueair models with HEPASilent's mechanical and electrostatic filtration produced higher CADR, lower noise, and had lower energy consumption vs. the same models with only mechanical filtration (H13 filter). Product Features ULTIMATE TOOL AGAINST WILDFIRE SEASON: Additional activated carbon removes 99.9% of wildfire smoke along with extra protection against other wildfire emissions such as toxic gasses, smog and odors COMPATIBLE WITH ENTIRE BLUE PURE 411 AIR PURIFIER LINE: Blueair 411 Series SmokeBlock Replacement Filter compatible with entire Blue Pure 411 air purifier line consisting of Blue Pure 411 Auto, Blue Pure 411, Blue Pure 411+ air purifiers FILTERS BUILT TO LAST: Using a 360-degree air intake and up to 4x the filter surface area the Genuine Blue Pure 411 Series 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 RECYCLABLE: Please check your local recycling facilities for availability Shipping: Shipping is complimentary within the lower 48 US States. We Do Not Ship to PO/APO Boxes, HI or Alaska We Do Not Ship Outside of the Continental US All items ship within 24-72 hours of Payment For large items that require Freight shipping a valid phone number is required to call and schedule your delivery Terms of Sale and Feedback: Feedback is extremely important to us and If you are satisfied with our transaction, please take a moment to leave Positive Feedback. YOUR Satisfaction is our #1 Priority! If there are any issues, PLEASE contact us BEFORE leaving a neutral or negative rating so that we may resolve any concerns. We PROMISE we can make you happy if you give us a fair chance. Returns / Concerns: All items qualify for returns within 14 - 30 days of receipt. Buyer is responsible for return shipping on any item that is not damaged Please be sure this is an item you want before making your purchase. Customer Satisfaction is our TOP priority! All items are IN STOCK at time of listing. Inventory changes constantly and it is impossible to maintain a perfectly accurate count of all items. Please do not penalize us if we have to issue you a refund! Thank You For Your Business!