USB Meter, DROK Digital Multimeter USB 2.0, Multifunctional Electrical Tester, Capacity Voltage, Current Power Meter Detector Reader with Dual USB Ports, LED Display, 7 Modes 7-MODE USB MONITOR ---- voltage measuring range DC 3.20~30.0v; current measuring range 0.00~3.00A (10A max.); other measuring parameter: capacitance, power going to your phone/battery pack. With 7 mode, one button to operate. MULTIFUCNTION ---- can be used for capacitance checking, capacitance clear, over voltage and under voltage alarm, over-current, and short circuit alarm, easily test the power/quality of the chargers and USB cables. DUAL USB OUTPUT ---- two USB output available, can be used simultaneously. Output I: be used for device charging and data transfer; output II: only for charging mobile phones, tablet PCS and etc. Output I Support QC 2.0 9V & 12V charging, but don't insert any device in Output II when using QC 2.0 Charging. DUAL COLOR LED ---- with red and blue dual bright color LED display, easy to monitor the charge voltage and current of digital USB devices to ensure the optimal charge rate. 100% RISK-FREE SATISFACTION GUARANTEE ---- DROK offer you 100% risk-free satisfaction guarantee to let you buy with confidence.