Features: Color screen display: The color screen display makes it easier for you to read and identify in darkness. Wide application: The portable size enables you to take it anywhere you go. It can be used at the home, office, shopping mall, hotels and etc. 3 in 1: It can detect real-time CO2 concentration, humidity, and temperature. CO2 detection range: 400-6000PPM. Temperature detection range: 0-50. Humidity detection range: 0-99%RH. CO2 detector: The color ring will change according to the current CO2 concentration. USB charging: Connect the power supply and then it will start to work. Any problems, feel free to contact us. Honor to serve you Specifications: Name: CO2 Meter Color: Black Material: ABS 3in1 Detector: CO2 Concentration/Temperature/Humidity CO2 Detection Range: 400-6000ppm CO2 Accuracy: 1ppm Humidity Accuracy: 2%RH Power: 0.4W Battery: 3.7V 1500mAh Charging Time: 2-3h Work Time: 6-7h Size: 89*70*35mm Package information: Size: 14.1*9.8*10cm Weight: 340g Packing List: 2* CO2 Meter 1* Charging Cable 1* Instruction