The real-time and accurate carbon dioxide detector uses the infrared light source (NDIR) absorption principle to detect the carbon dioxide content in the on-site environment, detect air quality in real time, monitor the healthy environment in real time, and pay attention to the health of you and your family. Multifunctional Thermohygrometer This air quality monitor's multifunctional design also has the ability to monitor carbon dioxide, humidity, and temperature. The large screen displays the PPM value of carbon dioxide. / can be switched between. Relative humidity keeps you informed of air quality. . Portable and space-saving Our carbon dioxide detector is small and easy to carry, and can be put into your bag for easy portability. The detector saves space and is suitable for indoor and outdoor use. It has a long battery life and a built-in 18500 lithium battery. It can work continuously for more than 8 hours after being fully charged. It can be charged directly using USB and can be used while charging, which is very convenient. Effective heat dissipation The hollow heat dissipation design on the back ensures that the sensor is in full contact with the air, which is conducive to heat dissipation, thereby reducing false alarms caused by high temperature and insufficient air contact. Specifications CO2 measurement range 0-9999 resolution 1 accuracy 703% reading temperature measurement range 20-60 humidity measurement range 0-99% temperature accuracy 2 humidity accuracy 3% built-in battery 18500 lithium battery working time can work continuously for more than 8 hours power supply USB/ 5V Size 80*80*55mm/3.15*3.15*2.17in Packing List Carbon Dioxide Detector*1 Instruction Manual*1 USB Charging Cable*1 Solutions to Frequently Asked Questions 1. Inaccurate CO2 measurement 1: The concentration and content of CO2 in the environment are not accurate Stable, please keep it in the same place for a while during the measurement process. 2: The carbon dioxide sensor sampling window may be blocked by debris and dirt, and the airflow window may be blocked by foreign matter. 3: The carbon dioxide sensor is biased and the equipment needs to be recalibrated. 2. Inaccurate temperature and humidity measurement 1: The sampling window of the temperature and humidity sensor may be blocked by debris or dirt. 2: The airflow window is blocked by something. 3. Unable to turn on the battery. The battery is dead or damaged. Please use the USB port for power supply. If it turns on and the battery charge changes, the battery is low. If the charge does not change, the battery is damaged. Commitment and Warranty We are professional sellers and promise to be responsible for all products, whether before or after sales. If you have any questions, please feel free to contact us and we will reply to you within 24 hours.