Features: 1.There are three functions,Set for time, temperature and voltage 2.Three functionscan be switched at any for time. 3.Total 4 kinds of display modes. 4.Only display for time/only display temperature/only display voltage/three of functions alternate display (Note: in the alternatedisplay mode, can choose whether to display the temperature or voltage,through the dd option under the condition of dd:0 display for time + temperature+ voltage. dd:1 display for time + voltage. dd:2 display for time + temperature). 5.Manual correction function with temperature error, setting range of -5~5. 6.With a backup battery, power down for time to continue to go. Specifications: Voltage:5-30V (to use the voltage meter function, the input voltage of at least 7V above) Voltage meter range: 7 ~ 20V ( error 0.1V, measuring voltage=input voltage) Temperature measurement range : -50 ~ 130 (the original temperature range from -9 ~ 60 ) Current :about 30mA Size:40mmx13mm Thickness:14mm Application: especially suitable for 12V car Note: 1.Recommended more than 5.5V power supply, not according to the standard of power supply voltage, will burn out, the need to install the power supply wiring 2..Please allow 1-3mm error due to manual measurement. Please make sure you do not mind before you bid. 3.The colors may have different as the difference display, please understand. Package include: 1 x Digital Car Clock Time+Temperature+Voltage 3 in1 Meter