[Jon Stratis]

If you look at the specs for heat shrink, it'll specify an inside diameter both before and after shrinking. You'll want to get some that is big enough to fit over everything, including the nut and bolt, but that will shrink down to a snug fit without splitting. I've seen students use the wrong heat shrink a few times... it looks good, then they put the heat gun on it, and it splits because it tries to shrink too small for the wire it's around!