NWT/Open If you are NEW to Poshmark, save $10.00 by using ... JENH359 ... as a referral!!! 9" Tall BLUEAIR Blue Pure 411i Max and 411a Max Genuine Replacement Filter, Blue Pure F4MAX, fits Blue Pure 411i Max and 411a Max Air Purifier BLUEAIR GENUINE FILTER: For Blue Pure 411i Max and 411a Max air purifiers; Blueair genuine Blue Pure F4MAX Replacement filter for 411 Max Series is designed for optimal performance; Not compatible with 411, 411+ and 411 Auto LET’S CLEAR THE AIR FASTER: HEPASilent dual filtration technology delivers more clean air faster and uses less noise and energy than HEPA filtration alone* LET’S CLEAR THE AIR BETTER: Removes at least 99.97% of tiny airborne particles like viruses and smoke down to 0.1 microns, and captures pet dander, pollen, mold allergen and dust; carbon filter traps light household odors from smoking, pets and cooking** MOST AWARDED AIR PURIFIER BRAND IN THE US***: Independently tested for performance, Zero Ozone; AHAM Verifide for Performance (CADR); Quiet Mark Certified; Ozone Safety Standards Certified by CARB; Zero Ozone Verified (<5 ppb) by Intertek Sustainability