1.MULTIFUNCTIONAL TESTER: Unleash the power of this automotive electrical system diagnostic tester that goes above and beyond! From voltage and resistance testing to polarity checks, continuity testing, signal circuit analysis, and even component activation – this tool can do it all. Say goodbye to long diagnosis times and hello to streamlined electrical system troubleshooting. 2.POLARITY PRECISION: Experience nextlevel detection with the innovative sensitivity probes of the power circuit probe tester. A simple touch of the probe tip lights up red for positive polarity and green for negative. Seamlessly test continuity and execute jump operations with ease using the included auxiliary ground wire. 3.USERFRIENDLY DESIGN: With a 4.5m extension lead, you can effortlessly test the entire vehicle's electrical system from front to back. Clip the red and black clips onto the battery poles, and let the builtin LED light guide you through dark or dimlylit spaces. The resolution color display ensures crystalclear data viewing for a comfortable diagnostic experience. 4.SAFETY RELIABILITY: Stay protected with the builtin overload safeguard that ensures your tool's longevity. Before testing, the tester performs a quick selfcheck to guarantee performance. If the current surpasses 7A, the circuit tester automatically disconnects and sounds a buzzer alert for your safety. Ground connection checks can be performed hassle, directly and efficiently.