Compatible Models: Perfect compatibility with 𝐁𝐥𝐮𝐞 𝐏𝐮𝐫𝐞 𝟑𝟏𝟏𝐢 𝐌𝐚𝐱 air purifier, can be used as Replacement Part for # 𝐅𝟑𝐌𝐀𝐗.✖✖✖. 𝐍𝐨𝐭 𝐜𝐨𝐦𝐩𝐚𝐭𝐢𝐛𝐥𝐞 𝐰𝐢𝐭𝐡 𝐁𝐥𝐮𝐞 𝐏𝐮𝐫𝐞 𝟑𝟏𝟏𝐢+ 𝐦𝐚𝐱 𝐨𝐫 𝟑𝟏𝟏/𝟑𝟏𝟏 𝐀𝐮𝐭𝐨！Please note that the ✖✖✖𝟑𝟏𝟏𝐢+ 𝐦𝐚𝐱 𝐚𝐧𝐝 ✔✔✔𝟑𝟏𝟏𝐢 𝐌𝐚𝐱 𝐥𝐨𝐨𝐤 𝐞𝐱𝐭𝐫𝐞𝐦𝐞𝐥𝐲 𝐬𝐢𝐦𝐢𝐥𝐚𝐫, 𝐛𝐮𝐭 𝐭𝐡𝐞𝐲 𝐚𝐫𝐞 𝐭𝐰𝐨 𝐜𝐨𝐦𝐩𝐥𝐞𝐭𝐞𝐥𝐲 𝐝𝐢𝐟𝐟𝐞𝐫𝐞𝐧𝐭 𝐦𝐨𝐝𝐞𝐥𝐬!They are completely different sizes too!Please check your model number carefully before purchasing. High Quality Material: Blue 311i Max replacement filter is made of high-quality non-woven activated carbon and can adsorb 99.99% of air particles (with a diameter as small as 0.03 micrometers), bringing a healthy environment to your family 3-in-1 Efficient Filtration：Blue Pure 311i Max Filter adopts double-layer filtration technology, which absorbs pet plush、household waste, volatile organic compounds and smoke components through pre filters and carbon filters, providing fresh air for your family Installation and Regular Replacement: Simply remove the packaging to replace the old Blue 311i filter without any tools. Recommended to regularly replace the Blue Pure 311 filter within 6-9 months to maintain The Freshness And Cleanliness Of The Machine Customer Service: Including 2 cost-effective Blue Pure 311i Max filters. NXBHG Store has been specializing in bringing each family freshing air with providing customers premium quality and affordable replacement filter. We highly value customers' shopping experience and If you have any problems while using this replacement filter compatible wtih 311i Max replacement filter, please contact NXBHG Store customer service team without any hesitation. We are ready to help you to solve problems within 24 hours NXBHG Blue Pure 311i Max Replacement Filter Compatible with Blue Pure 311i Max Air Pu-rifi-er, 3-in-1 High-Efficiency and Activated Carbon Filter, Part#Blue Pure F3MAX