Measure USB charging voltage, current, and discharge capacity over time Check the performance of USB cables, wall chargers, car chargers, and power banks Fast-charger compatible, works up to 20V and does not interfere with quick charge negotiation Voltage range: 4-20V • Max Current: 3A • Resolution: 0.01V, 0.01A, 1mAh mAh measurement survives power loss • Size: 7.25×2.5×1.35cm