1LED DIGITAL DISPLAY: The auto circuit tester uses LED digital display to accurately display automotive electrical parameters, which is clear and intuitive. 2MAIN FUNCTIONS: This test pen can be used to measure automotive voltage, current, resistance and other parameters, ensuring high accuracy diagnosis. 3FOR AUTO TESTING: This LED test pen is designed specifically for automotive diagnosis, convenient and fast to locate faults and ensure safe driving. 4PORTABLE DESIGN: The LED circuit tester is portable in design, compact and lightweight, comfortable to hold, convenient to carry and operate. 5EASY OPERATION: Equipped with spring wire and electrical clamp design, this circuit tester is easy to operate, greatly improves detection efficiency.