Here is a Keystone Watch Case Co FOB from the 1893 World Fair I recently picked up.

Here is the other side.

Ernie,
I just love these little things. I mostly use my larger case opener, but these are great for carrying around, and come in handy all the time.

Of course, I consider them a collectors item, but since I have more than one named fob, I can save one, and carry the other one for use! Nice!

The Keystone is very comfortable, I like the round shape, it's the easiest to use.