【Compatibility】: This 511i Max replacement filter is fully compatible with BLUEAIR HEPASilent Air Cleaner, Blue Pure F5MAX, and Model Blue Pure 511i Max. 【Attention Please】:This Filter is ONLY compatible with BLUEAIR HEPASilent Air Cleaner, Blue Pure F5MAX, and Model Blue Pure 511i Max. Not ❌compatible with 211+ and 211+ Auto, 411i max, 411a max,511, 311, 121, or other models, Please check the model number before placing the order. 【High Efficient Filltering】：The HEPA filt-er Clean at least 99.97% of tiny airborne particles like smoke down to 0.1 microns, and cleans pet dander, and dust, The activated carbon filt-er cleans up light households from smoking, pets, and cooking fume 【Performance Peak】：For your machine performance peak, based on actual usage the filter should be replaced every 6 months, it's easy to install, and no tools are required. 【We Treasure Our Customers】: If you have any questions about our product, please feel free to contact us, and we'll solve them within 24 hours. Filter made of FSC-Certified paper 2-pack 511i MAX Replacement Filter Compatible with BLUEAIR HEPASilent Air Cleaner, Blue Pure F5MAX, Model Blue Pure 511i Max