Having a scribe can be quite useful for working on cars or bikes. One example of their use is marking the alignment of two pieces – like a timing rotor and the surrounding case – in a way that can’t be rubbed off prior to separating the parts so that you know how to align them when it’s time to reassemble. Lisle make a scribe that’s readily available online and cheap to boot:
Part number 31800. It’s ends are heat treated steel and the handle is knurled aluminium, and one end is set at 90 degrees which can make scribing in tight spaces easier.
There are some varied reviews out there for the 31800 but so far this particular example has performed as expected, without either end detaching or breaking. You can find the Lisle 31800 scribe for sale on Amazon