Help identify these miniature thread cutting die collets?

[rockcrawl]

I have these two collets that hold a 13/16" round die. Anyone know what machine or tool they're for?

 

[FredC]

Mechanical Swiss machines used a lot of those kind of dies for threading. So my first wild guess is the collets were from the Swiss machine manufacturers or made for Swiss machines.

 

[camscan]

Mechanical Swiss machines used a lot of those kind of dies for threading. So my first wild guess is the collets were from the Swiss machine manufacturers or made for Swiss machines.

Not saying that you are wrong Fred but I have never seen them.

 

[FredC]

Not saying that you are wrong Fred but I have never seen them.

Like I said a wild guess, I have never seen the collets before. Just saw a Swiss machine once use a solid die. Figured they might use a collet like that. Would have been surprised if you said I was right.