USB Charger Doctor - In-line Voltage and Current Meter Reports voltage and current from USB port to help debug projects You can use this device from 3.5-7VDC input voltage (although most USB devices tend to hover around 4.75 to 5.25) and up to 3A of current USB 1.x and 2.x - all data speeds. Does not have USB v3 pins so USB v3 connections will automatically downgrade to v2 Genuine Adafruit Products come in small polly bag with Adafruit label/Amazon label over Adafruit's label Adafruit Part Number: 1852