4in1 3.1A Dual USB Car Charger,SENHAI Portable Fast External Charger Cigarette Lighter with Blue LED Display Compatible For Most Android IOS Windows Devices--Black FAST DUAL USB CHARGING PORTS - Combined 3.1 amps; 15W; uses smart technology to ensure each device pulls the right amperage. Charger is powered by the vehicle's cigarette lighter. OVER-CHARGE PROTECTION - auto power off when input/output is greater than safety current, protects against over-heat, over-current and over-charging LED DISPLAY - LED digital luminescence tubes.Display cycles between internal temperature (Fahrenheit), device's charging current, and the voltage of the vehicle's car battery. The LEDs are bright enough to read the display without being a distraction while driving.(Note: When using the device to charge, it display the charger's temperature instead of the internal temperature of your car. )