Nispira premium filter set compatible with Blueair Blue Pure 411, 411+ & MINI Air Purifiers. High quality HEPA filter captures 99.97% of airborne particles size down to 0.3 microns. Activated charcoal filter helps deodorize any unfavorable household smell and chemical VOCs 1 Filter included. Dimension: 1.9 x 8 x 11.1 inches. Suggested to replace every 6 months for best performance. 100% customer satisfaction guaranteed. Quality meets or exceeds leading national brand Nispira Premium Foldable HEPA + Activated Charcoal Air Filter Replacement Compatible with Blueair Blue Pure 411, 411+ & MINI Air Purifiers. 1 Filter included. Dimension: 1.9 x 8 x 11.1 inches. Suggested to replace every 6 months for best performance.