There’s a few items that most every car guy or gal have in arms reach at all times when working in their shop. For me one of those is Sharpie marker. They work great to write notes on things as I work or to mark out measurements, trace lines for bead rolling, etc, etc. These work great when sharp, but they tend to wear out and get dull quickly. The more dull they get the wider the mark will be that it leaves.