I think it is a watch. Could be a: Metal detector Oven Or meat mincer But I think it's a watch Do you have any other pictures? What has your research discovered so far?
What he's saying is without a little peek at the numbers on the inside of the back case and a view of the movement it's hard to be precise. Do you have possession of the piece? If so take it to a watchmaker and have them remove the back and take pictures of the numbers in the cap and on the movement if possible. Could be a lot of things the way it looks right now.