CO2 monitor are smart, compact and easy-to-use. In addition to measuring the CO2 concentration, they can also measure the ambient temperature and the relative humidity (CO2+Temp. +RH). These products are developed to detect the presence of CO2 in ambient air and help people to take care of Indoor Air Quality. they can be widely used in the office building, school, exhibition hall, shopping mall, meeting room, fitness center, restaurant and other public places where personal comfort, healthy is important.