Multifunctional USB tester with non-volatile memory and great features in a small case. Used to control the capacity, voltage, current, power of various devices: power banks, batteries or other devices charging via USB. It can count the charge given or received in milliampere-hours (mAh) watt-hours (Wh), and also counts the amount of time during which the current was consumed. Display on the LCD screen: - Voltage 4-30 V - Current Strength: 0-5 A - Capacity: 0 ~ 99999 mAh - Power 0-150W - Energy 0-999,999Wh - Charge / Discharge Time: 0 - 99 hours - Temperature ° C.