This replacement air particle filter is a compatible replacement for Blueair models 201, 203, 203C, 205, 205C, 210B, 250E, 270, 270E, 303, and other 200/300 Series models. Part # 200PF, 201PF. It is compatible with all Blueair 200 Series Air Purifiers as well as the Blueair 303 Air Purifier. Any brand names or logos are the registered trademarks of their respective owners. This filter is absolutely essential for allergy sufferers: Helps effectively filter airborne irritants such as smoke, pollen, dust, mold spores, pet dander and fabric fibers. 4 Stages of air cleaning! Brand names and logos are the registered trademarks of their respective owners. Any use of brand names or model designations for this product is made solely for purposes of demonstrating compatibility.