Worldoor Hot Sale Dual-USB 2.0 HUB Charger Doctor Voltage Current Detector Digital Ammeter Voltmeter Multimeter Fast Charging and Solar Panel Alignment USB Tester Mobile Power Panel Monitor Gauge DC Display 3.2-10V 0-3A Red Blue LED Display Operating Current: &lt;20mA; Display: 0.28 "LED, Red/Blue; Accuracy: 1% ( 2 digits)