I picked up some threaded aluminum pieces, not sure what they are for. They are labeled 1, 2, 3, 4, & 8, although the threaded size doesn't really follow the numbering.
You leave them all in your high school auto mechanics class one day, and watch everyone try to find 5,6, and 7. Joke's on them tho, because there IS no 5,6, or 7!!!!!