Features_x000D__x000D_- Portable, light weight, small size and durable._x000D_- Easy to measure the USB charging current, voltage, discharge capacity_x000D_- High temperature can be used for measuring USB powered or power consumption of the interface , mobile phone charger , U disk and other products._x000D_- Regular power off. When it's showing 00:00H on screen, press and hold the button for about 3 seconds and there will be flashing numbers on the display. Press the button for 0.5 second and each time you press the button, it will add 0.5 hour. Then press and hold the button for about 3 seconds to save._x000D_- With precision current calibration function for higher current accuracy_x000D__x000D_ Specifications _x000D__x000D_- Color: Black_x000D_- Material: Plastic_x000D_- Size: 7.3x2.8x1.5cm_x000D_- Accuracy: ±1%_x000D_- Connectors Supported: USB_x000D_- Voltage: DC 3-9V (0.01V resolution)_x000D_- Current: 0-5A (0.01A resolution)Packing list: 1 x USB meter