4 stages filtration system:
Pre-filter stops cotton fiber, furs, dust. Anti-bacterial layer kills 99.9% of bacteria. Effective particles filter captures 99.5% of pollen, PM2.5 and other fine particles, as small as 0.1 μm. Activated carbon traps formaldehyde, TVOCs, and odors. Applicable for multiple Mi air purifier models: 2, 2H, 2S, Pro, 3H etc. RFID equipped. 3 to 6 month life time, which can be checked from Mi Home app.