Unknown widgety things

Whilst having a bit of a clearup at home, I found a small bag of these widgety things and I have no idea what they are. (Obviously, I know what the fifty pence piece is. That’s included just for scale. D’oh.)

The long cylindrical one I’ve shown from both sides to show how each end differs but altogether there are:

• 8 metal cyclindrical pieces
• 10 black rubber footer-type pieces
• 2 of the thinner metal pieces

None of the pieces fit together in any kind of obvious way. So, for a chance to win the fifty pence piece as shown, what are these things supposed to be for?