Multifunction: It displays the temperature inside and outside the car, battery voltage and time/date display. Universally suitable for DC 12V / 24V vehicles. Powered by a cigarette lighter charger or 2 LR44 batteries (included), 2 button batteries are included. The green/blue backlight can be switched to orange. Adjustable to 180 degrees, comfortable to read with large LCD screen. Easy installation with double-sided adhesive tape.