Item Type: USB C Power Tester Product Material: ABS Product Model: KWS-1902C Colour: Black Voltage: DC4-30V Current: 0-5A Capacity: 0-999999mWh Load Resistance: 1-9999.9 Voltage Resolution: 0.002V Current Resolution: 0.002A Power: 0-150W Product Interface: USB C 24pin Display Screen: 0.96in Color Screen Test Direction: Two-way Support: QC2.0/QC3.0 Applicable Temperature: 0-80 Timing: 0-99 hours Product Size: Approx. 55 x 26.5 x 6mm / 2.2 x 1 x 0.2in How to Use: 1: Single short press once to change the display page; 2: Quickly double-click the button to rotate the display page 3: Long press the button for 3 seconds to clear all saved data; 4: Charging Flow Direction Indicator: The color of the arrow and the scroll speed follow the current; Small but changes, the order of current from small to large: green, yellow, orange, red, the larger the current, the faster the scrolling speed, and the flow direction indicator will not be displayed when there is no current. 5: Current and Voltage Calibration Method: You must use a standard voltage of 5.000V to press and hold the button to power on. When the "Factory setting" is displayed on the screen, you can release the button and the product will automatically calibrate. Calculation Method of Mobile Power Capacity: The mobile power supply is fully charged and connected to KWS-1902C(data cleared first) and electrical appliances, and discharged until it stops output. Method 1: Mobile power capacity = KWS-1902C Measured mAh Data x Output Voltage + Battery Voltage + Efficiency Method 2: Mobile Power Capacity = KWS-1902C Measurement mWH: Battery Voltage Efficiency (General mobile power output voltage is 5V, battery voltage is 3.7V, efficiency is about 85-90%)