- Flexible spring wire and large clip: High quality long spring wire increases testing flexibility; the tail wire bend design prevents poor connections; large-size clips enable one-handed operation, improving efficiency in car battery capacity inspection and other tasks. - Expanded voltage capacity and wide range of uses: The tester covers 5V-120V for quick car battery voltage checks and charging-system issues, including an alternator tester function for car/truck/SUV/marine systems; can also check the integrity of circuits such as headlights, taillights, and connections. - LED digital display: LED digital voltage readout provides accurate readings and remains clear in daylight or dark environments, independent of ambient brightness. - Bidirectional indicator light: The circuit board includes bidirectional LEDs to indicate polarity, with red for positive and green for negative. You can connect the clip to the negative or positive ground while testing the opposite side with the probe. Use scenarios: - Quick battery and charging-system diagnosis on cars, trucks, SUVs, and marine equipment to confirm voltage levels and detect alternator issues. - Inspect electrical circuits such as headlights, taillights, and wiring connections for continuity and reliability during maintenance. - Work in tight spaces or one-handed operation situations thanks to the flexible wire and large clips for easy handling.