Carbon Filter, Dust Filter
Blueair Blue Pure Genuine Replacement For 411 411+ 411 Auto Air Purifier Filter in White | 11.4 H x 7.9 W x 2.5 D in | s- White
Amazon
BLUEAIR Blue Pure 411 Auto, 411, 411+ Genuine Replacement Filter, Particle and Activated Carbon, fits Blue Pure 411 Auto, 411 and 411+ Air Purifiers