Blueair 501FILT/3PK Classic Replacement Filter, 500/600 Series Genuine Particle Filter, Pollen, Dust, Removal 501, 503, 510, 550E, 555EB, 601, 603, 650E, 505, 605

The gradient structure of Blueair filters traps particles of all sizes while maintaining maximum airflow. It resists clogging and won't re-release particles back into the air, even when the filter is heavily loaded. Blueair filter media is...