Autowit Fresh has a detection sensor that automatically senses air quality and can automatically detect indoor air pollution. Sensitivity is divided into three levels: when the air is good, the light is green; when the air is lightly polluted but at an acceptable level, the light is yellow; when the air is heavily polluted, the light is red. If the automatic mode is set, the air purifier will automatically adjust the wind speed according to the pollution to maintain a good purification effect.