I have been sent this by a metal detectorist who did not want it. It is the size of a medium pocket watch but does not appear to have ever been one.
The reason for posting here is simple. I was sent it because the finder believed it is military in origin because of the 'US' stamped on it.
I have to say, it is the same style and font as military items stamped 'US' and I to believe it may be military in origin.
Any help would be greatly appreciated.