DROKxae;&trade DC 3.2-30.0V Digital Panel Voltmeter Gauge Car 12V Battery Volta. Power supply: direct use of the test voltage as a power supply Measuring range: DC 3.2 - 30.0V Measure accuracy: (1% + 2 Digit) Display mode: Three 0.36 LED digital tube Dimensions: 35 * 23 * 20mm