Ever wondered how pros test auto wiring without stripping wires? This Harbor Freight kit helps you do it, like they do, without zapping yourself.

The ICON Digital Circuit Tester is a new test light that is available at Harbor Freight. Unlike an old-school device, this light provides a bright red (positive) or green (negative) LED numeric ...

As well as building real-life circuits you can also use circuit simulation software on your Mac. This enables you to test out parts and components in a safe environment.