Features: CO2 monitors uses NDIR technology to monitors indoor and outdoor CO2 concentration, the detection range- is 400-5000PPM. The mini CO2 meter can monitors CO2 concentration in real-time ,at the same time-, this CO2-detector with large full color LCD-screen design is easy to read. The portable carbon dioxide detector- is lightweight and compact-, easy to carry, with an anti-loss hanging- rope, allowing you- to keep informed- of environmental changes around you-. The CO2 monitors with three buttons- design,The M-key- can adjust the brightness, the Power-button can turn on or off the device, The S-key- long press to calibration data. The CO2 detector- built-in a 700mAh high-capacity rechargeable battery ,You- can long -time to use it in indoor and outdoor monitors air-quality arround you-. Specifications: Material:ABS Charging: Type-C Interface- CO2 Detection-Range: 400~5000PPM Working Voltage:3.7V Battery Capacity:700mAh Working humidity:0-95%RH Data refresh-frequency:2S Working temperature:-10-50Degree Preheating time:35S Screen Size:1.9'' Color: White,Black (Optional) Size:Approx.85x50.6x17mm/3.4''x1.9''x0.6'' Package Includes: 1x CO2 Meter note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item.