Features: The device can be used to test battery voltage, avoiding the overuse of power to affect the starting of your vehicle. Can be used to detect temperature in your car, making sure you are in a comfortable environment. Clear LED dual display, blue color for voltage display, red color for temperature display, easy to read the number. USB fast charging port, can charge your mobile phone, cigar lighter type, plug and play, convenient and practical to use. Uiversal fit for 12V cars, SUVs, and 24V trucks and buses. 3 in 1 function: Car voltmeter, car thermometer, USB mobile phone charger Specifications: Voltage: 12/24V Voltage/Current Output: DC: 5V/3.5A 9V/2.5A 12V/2A Temperature Measuring Range: -10~80 Diameter: 4.6cm Total Length: 7.5cm Material: Plastic Color: Black Package Weight: 46g/1.6oz Size: 7.5*4.6*4.6cm/3*1.8*1.8in Package List: 1*Digital Voltage Temperature Monitor Note: To measure accurately the temprature, the temperature sensor is external to the product. While using it, you can bend the sensor a little to avoid the hot parts of the car that may affect the measurement results(such as the parts that are exposed to the sun).