Here is no. #3

Frank,
I think these are the removeable jaws found in a pin vise. They are inserted into the body of the vise and a collet with internal threads is tightened over the jaws to grasp the material being held.

Ed
The largest one I have measures 1 5/8"X 5/16", that being the length of the tube and the diameter of it, not counting the head.
Do you still think that would be for a pin vise. I can see what you mean by the application of this tool as relates to a pin vise. Any luck on the id of the other pics.

Frank

Mine must be a slightly smaller version. The collets measure 1 3/8 inch long. The active collet goes in the threaded end of the handle and the other collet is stored in the tail end.

Jerry & Ed
Thanks for your help. I think the jaws I have must be for a pin vice used in Clock repair. I have a few of the smaller pin vices that are suitable for Watch work.

Frank