2 pack Compatible with 211+ Auto Models: These 211+ Auto true HEPA filters are compatible with Blueair Blue Pure 211+ Auto Air Purifier. Features: 1. Replacement Blue Pure 211+ Auto filter. 2. Reinforced HEPA Filter Material. 3.High efficiency and longer filter life. 4.Help promote a healthy living environment 5.HEPA Filter Dimensions: 11.7"x 11.7" . 6. To maintain maximum filtering performance, the filter should be replaced once or twice per 6-8 months, depending on use and local air quality. Package Included: Save more your money with 2 HEPA filters with Activated Carbon. Please Note: This product is not an OEM product. The brand names and logos are the registered trademarks of their respective owners. Any use of the brand name or model is solely made for the purposes of compatibility.