GEREE 0.4 inch USB Tester Monitor - USB Mini Charger Doctor Current Test Tool,USB Meter 2.0/3.0 Amp Volt LED Reader Premium Quality Low Cost Solution to Check USB Charging Current and Voltage in Instantly. Extremely Portable, Light Weight, Small Size and Durable, No Extra Cable or Power Supply Needed. Must Have Gadget for DIY Fans and Hi-Tech Lovers to Charging USB interface Electronic Devices Faster. Widely 3V-8V Voltage and 0A-3A Current Test Range Support with Accurate Readings. Detect any USB charger such as PC USB, home charger, car charger. All-In-One Piece without Blocking Other USB Ports When Monitoring USB Charging Current or Voltage.