Features: There are 6 types you can choose, black 3 in 1, black 5 in 1, Black 5 in 1 with infrared, white 3 in 1, white 5 in 1 and white 5 in 1 with infrared, just select the one you prefer to. for Smart carbon dioxide value tester gas analyzer uses air semiconductor TVOC sensor to monitor temperature and humidity of air quality. The product does not need calibration, it can be tested after booting, and it can accurately detect carbon dioxide. for Smart carbon dioxide value tester gas analyzer uses air semiconductor TVOC sensor to monitor temperature and humidity of air quality. Equipped with a large screen, different font colors display different air quality, 0-800ppm: green, 800-1200ppm: yellow ,1200-2000ppm : orange, 2000-5000ppm: red. Can be widely used in home, edcational institution, fiteness venue and office. Specifications: Material: ABS Plastic Color: Black/White Package Includes: 1x Carbon Dioxide Detector. note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.