Xiaomi High Efficiency Mi Air Purifier Anti-formaldehyde Air Filter WiFi Remote ControlKey Features...Activated carbon filter can effectively filter peculiar smell, formaldehyde, PM2.5, etc.High efficiency 3 layers filter: Primary filter net, EPA filter net, high quality activated carbon filter.The filter can remove 99.99 percent of PM2.5 particles, bacteria, heavy metal, organic matter, etc.Suita..