Rotary vices!

What’s this little round sping for? You know what I’m talking about? On the shaft before the jaws, that sping!! What’s it for?

Much thanks:)
Shane

Material clip to hold materials out of the way.

That makes sense. Now I feel stupid:)

Thanks a lot:)
Shane

And it is a Godsend at times!

Specially the Thread and wire for ribbing. But in no way feel stupid for that question.