SMART SENSOR LCD CO2 Monitor Carbon Dioxide Tester Multifunctional Air Quality Detector USB Rechargeable CO2 Meter Temperature Humidity Monitor 80000 Groups Data Logger Air Analyzer Multifunction carbon dioxide monitor, provide high accuracy and high stable real time CO2 concentration data, and also display temperature, humidity, dew TEMPM, Wet Bulb TEMPM, and current time and data. 80000 groups history logging function allow you to do detail analyse. Fully Customizable Setting for easy and covenient use, with Audible and light alarm. Features: Professional CO2 Monitor -- Versatile carbon dioxide detector can detect CO2, temperature and humidity. This air quality monitor adopt advanced ARM core chip with high stable and accuracy. It's detection accuracy up ±(50ppm+3% reading). Audio and Visual Alarm -- As the CO2 concentration is over setting value the CO2 tester will ring and change ligh to reminding you. 2.8inch True Color Screen -- Large clear FPC true-color display screen simultaneously display CO2 concentration, temperature and humidity, date and time. Special designed with 6 colorful section to indicator the CO2 concentration range, easy to know the air qaulity just for a glance. Data Logger -- Customizable recording start and finish time, also include recording interval (hour-minute-seconds). Built-in storage for continuous data logging, you can track trend data up 80000 groups data for co2 concentrations, temperature, humidity. USB Rechargeable --- This model now has a rechargeable 1500mAh lithium battery battery. You can press "LIGHT" button to turn off the monitoring and it will keep testing, and can carry on 24 hours uninterrupted monitoring to air quality if you plug into adapter to charge it. It will always take care of your breathing. NOTE: use computer download analysis recording data please download computer software via the U disk. Specification: Model: ST8310A Product Name: CO2 Tester Color: White Display: 2.8in FPC true color screen CO2 Testing Range: 0-20000ppm Resolution: 1ppm Accuracy: 0-10000ppm (±50ppm ±3% of readings)                  10000-20000ppm (±200ppm ±10% of readings) CO2  Concentration Testing Range: 0-2.000% Resolution: 0.001% Accuracy: 0-1.000% (±0.005% ±3% of readings)                  1.000%-2.000% (±0.020% ±10% of readings) Date Storage Capacity: Max. 80000 groups Sampling Rate: Customizable Alarm Mode: Audible Light Alarm( Green/Yellow/Red ) Alarm Value: Customizable Rechargeable Battery: 3.7V 1500mAh USB Input: DC 5V Temperature: -20℃ - 125℃ ( -4℉ - 257℉) Unit: ℃/℉ Switcheable Humidity: 0-100% RH Dew Temp: -20℃ - 60℃ ( -4℉ - 140℉) Wet Bulb Temp: -5℃ - 60℃ ( 23℉ - 140℉) Item Size: 146 * 80 * 68mm/5.7 * 3.1 * 2.7in Item Weight:  211g/7.4oz Packing List: 1 * Carbon Dioxide Detector 1 * Power Adapter 1 * USB Cable 1 * U Disk 1 * User Manual