This is a kind of fine quality air quality detector, which is adopt professional electrochemical sensing module, high accuracy, stable performance, antijamming ability, low consumption and can provides long service time. Accurately detect CO2. Large display, you can see the electricity quantity, CO2 value, TVOC value, HCHO value, temperature, and humidity clearly. You can have a try. Features: Adopts digital temperature and humidity sensor, high accuracy, stable performance, antijamming ability, low consumption and can provides long service time. Large LCD display, you can see the electricity quantity, CO2 value, TVOC value, HCHO value, temperature, and humidity clearly. and switchable, and the alarm sound can be on or off according to your demands. Equipped with environmental quality judgment function, it will display appropriate level according to measuring value. Built-in 1800mAh capacity lithium battery, easy to charge it with USB cable. When the battery is too low, the battery frame flashes to remind you to recharge it. New Function: Added a 30-minute automatic ON/OFF function, which can be canceled manually, just press the "+" and "-" buttons at the same time, and then you can hear two beeps. The main reason is to prevents the product without electricity from being shipped to customers. Specifications: Name: Air Quality Meter Material: plastics Display: LCD display Battery: 1 * built-in lithium battery, 3.7V, 1800mAh (included) CO2 measuring-range350-2000ppm TVOC measuring-range0.000 mg/m-2.000 mg/m HCHO measuring-range0.000 mg/m-1.000 mg/m Temperature measuring-range: 0-90.0(32-194), 1/1 Item size: 176 * 73 * 29mm / 6.93 * 2.87 * 1.14in Item weight: 222g / 7.83ounce Package size: 234 * 180 * 47mm / 9.21 * 7.09 * 1.85in Package weight: 461g / 1.02lb Packing List: 1 * Air Quality Meter 1 * USB Cable