RioRand USB Tester Multimeter Mobile Power Supply Doctor USB Voltmeter Ammeter DC Voltage Current Detector Power Monitor Volt Amp Panel Meter for Solar Panel Powered by RioRand Advanced Technology DC Voltage Current Detector, Measure Volt Amp and Data Communicator 2in1 Mobile Power Supply Charger Doctor, Compatible with Apple & Andriod Product DC Volt Ampere Amp Power Monitor USB Tester ,Solar Panel, Main Charger Monitor Multimeter DC 2.5-9V, 0-3A, with Overvoltage and Overcurrent Protection