Features: 1. Wide Application: Applicable to various fields such as shipbuilding, chemical engineering, agriculture, laboratory, mountaineering, pharmacy, etc.2. Automatic alarm: When gas is detected, the air quality monitor will give an alarm and the TVOC detector can set high and low alarm values.3. Highly sensitive sensor: With good sensitivity and excellent repeatability. Short response time, accurate and professional CO2 detector for home use.4. Rechargeable Design: The lithium battery of this air quality detector supports USB charging via computer, car, power bank, etc.5. High-definition display: Clear reading ensures no difference between day and night, clear and visible values, no fear of sunlight or dim light at night. Specification : Item type: Air quality monitorCO2 measuring range: 400 ppm ~ 2000 ppmTVOC measuring range: 0.000 mg/m ~ 5,000 mg/mHCHO measuring range: 0.000 mg/m ~ 1.000 mg/mTemperature measurement range: 0~90.0Humidity measurement range: (0~99.0)% RHBattery: Rechargeable 3.7V Lithium battery, 2000mAh. Comes with built-in battery. How to Use: Use according to the instruction manual. < p>Package list: 1 x Air Quality Monitor1 x User Manual1 x USB Cable