uxcell DC 0-30V LED Panel Digital Voltmeter Meter for Cars Motorcycle 9V 12V 24V Voltage Monitor Tester 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 3V to 30V. Widely used in autos, aircraft, test instruments, hydro power system. Fit for voltage indications and monitoring electrical systems.