Multifunctional 4-in-1 Car Digital Clock, In/Out Thermometer, Voltage Monitor This car digital clock and thermometer and voltage monitor lets you have the real-time crucial information when you're on road. It inspects batter storage as the voltage is excessive or too low. Audible and visual alarm when voltage is either too high or too low. It inspect your automobile at real time effectively, there is alarm lamp to remind you of avoiding damage as the temperature is lower than freezing point. Audible and visual alarm when voltage is either too high or too low. The clock can display 12 or 24 hour format. Measurement of the temperature display in Celsius degrees.