Unique US Map for your RV?

by David

OK, this might be hard to explain, but here goes...Many years ago I saw a small brass (?) "plaque" of the United States that you could attach somewhere on your RV. It had a "hole" in each state where you could put a "jewel" in to show that you had driven through that state.

I know that's not a real adequate explanation of what I'm looking for. But does anyone know what I'm talking about and if so, where I could find it online? Appreciate any thoughts!