What are these for?

kjhgfds

You answered your own question. You cut them to length to fabricate bushings. They are used in many places on a RV-10, as I would also expect to see on a RV-14.

Pieces parts

Were they listed on the inventory page for that bag? If so you could track them down by either their name or part number. I'm pretty much done with my wings and don't recall seeing those. All my bushings were pre-cut to the right length so it would appear they are surplus.

I had them left over from my wing kit as well....along with other parts.