Shells Classy Black Mini 12V/24V DC Digital Car Motorcycle Cigarette Lighter Voltage Electric Meter Socket Battery and Charging System Monitor With Red LCD Digit Display Monitor About ShellsShells Group concentrate on providing reliable quality comsumer goods with affortable price. Used for DC 12V or 24V car only to test the voltage of batteries. Insert the jack into a cigar socket and no difficulty in seeing the display. With super bright LED to constantly monitor battery voltage, extend and protect the battery . Package including: 1PCS Black car battery voltage monitor.