uxcell DC 4.5-30V LED Digital Voltmeter Car Motorcycle Panel Meter Voltage Tester 12V 24V Battery Volt Accurate Detector Gauge This Voltmeter has LED display Screen for conveniently and easily reading. With reverse polarity protection function, line reversed will not burned. The measuring Range of this Voltmeter is from DC 4.5V to DC 30V. Widely used in autos, aircraft, test instruments, hydro power system. Fit for voltage indications and monitoring electrical systems.