The gradient filter structure resembles many filters in one, trapping particles of all sizes while maintaining maximum airflow. The progressive structure resists clogging and won’t re-release particles back into the air, even when the filter is heavily loaded.
Certified efficiency 99.97% for particles down to 0.1 microns such as dust pollen, bacteria, virus, pet dander, mold spores and other airborne particles.
These filters are designed to fit the Blueair 501, 503, 510, 550E, 555EB, 601, 603, and 650E units.