Wide Applicability: This USB Tester Measuring voltage: 3.7V-30V; measuring current: 0-4A. Supports QC2.0, QC3.0, iPhone 2.4A/2.1A/1A/0.5A, Android DCP/AFC, FCP(9V/2A)/SCP(4.5V/5A), fast charge protocol identification, let you know the charging status of the phone. Support for high current testing, support USB3.0 interface mobile hard disk and U disk test. Measuring Data is Guaranteed: Power-off storage function that stores capacity and energy data when the mobile power is turned off, which is convenient for subsequent viewing and convenient for capacity energy measurement of mobile power. Note: Other USB testers that do not have a power-down storage function cannot test capacity and energy. Varies of Display Modes: 6 kinds of display can be switched. Uses a 0.96-inch IPS high-definition color LCD display to display the state of charge of the appliance, voltage, current, capacity, energy, power, equivalent impedance, temperature and other indicators at a glance. 4-bit accuracy for more accurate measurements, 160 degree wide viewing angle, high brightness and long working life.