Features: Multifunction CO2 Monitor & Controller: it can detect CO2 concentration, temperature and humidity in the current environment, and realize the automatic control of carbon dioxide concentration. High-precision Split-Type Probe Sensor: high sensitive external probe sensor for quickly and accurately measurement of carbon dioxide content. Large Colored Screen: 3.8-inch screen display the current values in real time, and it has the human mode and plant mode to be switched from. Human Mode: if the set alarm value is exceeded, the instrument will automatically supply power to the exhaust fan for ventilation and beep sound-light alarm. Suitable for hospitals, offices, schools, stations, commercial buildings, etc. Plant Mode: when the set value is exceeded, the relay output will be turned off; and the relay output will be turned on automatically when it decrease to the preset low value. Suitable for greenhouse, agricultural, hydroponic flower industry, mushroom farm, etc. Easy to Install: the device with simple but stylish appearance, package includes the accessories for wall mounted installation. Specifications: Plug: EU / US (Optional) Material: ABS Power Input: AC100-300V CO2 Measuring Range: 0-9999ppm CO2 Display Resolution: 1ppm CO2 Accuracy: ??50ppm CO2 Repeatability: 10ppm CO2 Temp. Dependence: ??1% of reading per ?? or ??2ppm per ??, whichever is greater, referenced to 25?? Pressure Dependence: Support Response Time: Package List: 1 * Control Unit 1 * Sensor Unit 1 * S Hook 3 * Cable 4 * Screw 4 * Drywall Anchors