High Accuracy Monitoring: The professional 5-in-1 air quality meter has advanced sensors and recognition algorithms to accurately measure HCHO, CO2, TVOC, temperature and humidity data with low error, making it easy to understand the air quality around you. LCD Display and Alarms: The air quality monitor has a large color LCD display for clear reading even in dark environments. When the detected density value changes, the color bar changes in real time to remind the user of the color change. High Performance Battery: The air quality meter has a Built-in 1200mAh high capacity rechargeable battery which provides longer playing time, USB rechargeable, you can charge the air quality monitor via power bank, AC adapter, computer, PC, laptop. Wide range of applications: With a healthier family lifestyle, the air quality monitor automatically and accurately detects the concentration of CO2, formaldehyde and TVOC in the air. air, and is widely used in homes, cars, hotels, apartments, offices, cafes, libraries, outdoors, etc...