Battery

Hi and thanks for using 2CarPros.

If the negative cable "box" has a few black wires coming from it, you need to use the same thing. Those wires are grounds for specific components which require the best ground possible and are protected via fusible links.

Let me know if that is what you are looking at. Also, if it is not, can you upload a picture of what you have so I can get a better idea?

Take care,
Joe