The second generation UT658 series USB testers can inspect USB chargers, portable power sources, data cables and other electronics charging devices. Monitor charging efficiency at any time to protect charging equipment. UT658 measures output voltage, current, energy, capacitance, circuit equivalent resistance, D + and D-voltage of USB data cable, and more. This series is designed to be accurate, reliable, stable, and portable. They are great tools for applications such as production verification, engineering testing, and DIYers.