Can someone tell me what this is used for?

Got a picture or a link Bob ?
Respectfully,Bob Fullerton

The URL didn't show up on the last post. I'll try again.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5043933321&rd=1&rd=1

Just my own guess Bob,It looks like a lathe mounted file rest.The two rollers keep your file level when you are filing a flat on a pc. of material.Anyway it looks very similar to the file rests I've seen for sale at the marts.
Respectfully,Bob Fullerton

It must be a lot more than just a file rest. I have one of them and it a simple accessory. What in the world is it?

Regards,

Bob

To both Roberts,
I'm going to guess that this seller has stumbled
into a cache of really, really nice home made watch lathe attachments. The item in question is, I think, a file rest with the added capability of being able to adjust to file at angles. The other tooling offered by the seller
is made to a high standard but, again, not produced in a factory. This is really beautiful stuff though and a pleasure to see! Thank you for posting mention of it.-Cort