Features:  Digital Carbon Dioxide Detector: detects the carbon dioxide gas in the room through the absorption principle of infrared light source (NDIR), the test result is stable and accurate.  Lithium Battery Operated: built in 3.7V, 1500mAh lithium battery with USB interface, the meter is convenient to be recharged, no need to change battery, economical and environment-friendly.  2.0-inch LCD Screen: simultaneously display the real time CO2 concentration, temperature, and humidity, with clearly easy-to-read large white fonts.  Portable Size: features of light weight(4.5oz) and palm size, the CO2 monitor is compact and easy to carry. Also, it will no take up too much space of your countertop.  Wide Application: it can be used for the carbon dioxide testing in the field of agriculture, animal husbandry, industry, etc.    Specifications:  Material: ABS  CO2 Measurement Range: 370~9999  Resolution: 1  Accuracy: ±50 5% of reading  Temperature Measurement Range: -20~60℃  Humidity Measurement Range: 0~99%  Temperature Accuracy: ±3℃  Humidity Accuracy: ±5%  Battery: Built-in 3.7V, 1500mAh lithium battery  Working Time: Can work continuously for more than 8 hours  Power Supply: USB/5V  Item Size: 80 * 80 * 55mm / 3.15 * 3.15 * 2.17in  Item Weight: 128g / 4.54oz  Package Weight: 291g / 10.28oz  Package Size: 15.5 * 11.5 * 7cm / 6.10 * 4.53 * 2.76in    Packing List:  1 * Tester  1 * USB Cable  1 * Manual (English)