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    GSI Industries 4000 12-Volt Circuit Tester Tool

    Part #: CT

    The GSI Industries 4000 is a 12-volt circuit tester designed to quickly diagnose 6 V and 12 V systems. When connected, it can detect shorts, grounds, and open circuits on automotive wiring with power applied. Compact and user-friendly, it is ideal for mechanics, DIYers, and service technicians needing a quick check of live vehicle circuits.