I got a military surplus caliper set and I think that I want to sell
it on ebay. Does not seem like anything that I would need. (although I
acquired a mini electronic test equipment lab over time).

Here are the pix:

http://igor.chudov.com/tmp/calipers/

Any ideas what itis called and what i is for? It seems to be for
measuring some rotational angle. But what for?

i