【Multifunctional Carbon Dioxide Tester】This 3 in 1 CO2 monitor can detect real-time CO2 concentration, monitor indoor and outdoor humidity, and temperature. CO2 detection range: 400-5000PPM. Temperature detection range: 0-50℃. Humidity detection range: 0-99%RH. 【Intelligent WIFI Connection】The application we adopted is the most advanced graffiti intelligence technology in the market. You can monitor in real time after you connect your phone and our tester. Use the graffiti monitoring software to remotely check 3 indicators. Automation can advance CO2 calculations on the aggregated "air quality" metric. 【Full-Color Large Screen】With full-color display and large screen design, this carbon dioxide detector is super easy to read. LED digital display with intelligent backlight, eye protection function, one key operation. 【Large Capacity Rechargeable Battery】The CO2 detector has a built-in large capacity rechargeable battery, standby up to 40hours. You can check the air quality from anywhere, or have the device continuously monitor at a specific location. 【More functions & Multi Application】CO2 detector has Intelligent early warning system, high quality infrared NDIR sensor, multiple interference prevention and air convection technology, Suitable for agricultural planting, production warehouse, home, school, office, and other occasions. We 3 months free return and lifetime warranty for our CO2 detector.