Description     Display method:   LED Screen display   Atmospheric pressure: 86Kpa - 106Kpa   Sampling time: 1.5 seconds   Product Size:270*90*35mm   Detection temperature: -10°C to 50°C;   Relative humidity: 20% - 85%   Storage temperature: -10°C to 60°C;   Power source: Lithium battery with 2000 mAh capacity;   5V DC power charging   Product weight: 350g      This product is a decibel meter that detects，   Noise,Temperature, and Humidity. it combines sensors   real-time monitoring of decibel，temperature, and      Please read the instructions carefully before using this   device.   Please keep the manual handy for quick reference and     troubleshooting.            Avoid covering the air intake areas during use to avoid      inaccurate measurements.      Avoid use of solvents to clean the product as residual      fumes will skew air quality readings.      Avoid water or other liquids near the product to avoid      electrical damage.         Do not allow unauthorized modification or repair of this product.                 Features:         -Large screen LED display         -Support real-time testing of the concentration of decibel         -Large 2000mAh capacity Lithium battery         -             -Adjustable LED brightness           Noise indicator            30dB~65dB Green            65dB~85dB Yellow                 85dB~130dB Red Key operation Power button, Press to turn on/off Adjust the brightness-make it brighter Adjust the brightness-make it darker DC adapter input port LED display              Installation Notes              The positioning sticker is attached to the position to be               installed.               2)Punch a 6mm hole at the 2 marked positions of the               positioning sticker and drive the rubber plug into the wall.               3)Drive in the screws, and pay attention to about 4mm               exposed. Then hang the CO2 meter up.               4）Connect one end of the USB cable to the USB power               adapter, and the other end （round connector）to the               power input port on the side of the device(input voltage               ：DC5V)              Working method               Under normal working conditions, don't do any settings,               just plug USB port to the power adapter and the DC               round head into the device. You can test the current CO2               value and temperature and humidity in real time.               Automatic calibration               During the first use, please Turn on device and keep               more than 24 hours, the device will automatically               calibrate.