Measure the voltage of your car and, with convenient to scale, fast to charge your cell phone, compact, mobile power supply to prevent the car interior temperature Temperature sensaheddo for excessive, easy to be used and hidden support plug and play, convenient to use LED display, easy to read Specifications Input Voltage 12/24 V Working temperature: -20-60 °C Maximum output current 2.1 a output voltage V measuring range 9 ~ 80 °C car, SUVs, Truck, Bus, etc. Apply to your V/24 V battery to plug in to the cigarette lighter socket joint.