This air purifier features an odor sensor and automatic operation mode that adjusts the fan speed according to the odor level of the room, and a convenient auto shut-off timer at 1, 2 or 4 hours. There is also an air quality monitor that allows you to check your room's air quality at-a-glance and a filter replacement indicator to remind you when it is time to replace your filter. The high performance HEPA-type filter removes pollen, tobacco odor**, dust, mold spore, tick corpse, garbage & pet odors, nitrogen oxide, sulfur oxide, and can last up to 2 years under normal operating conditions. Includes a remote control.