This is a custom set of coins machined by Todd Lassen. The fit and finish is top-flight as you can see by looking at the Quarter in the top picture. It is the gaff!
The second picture is an exposed view of the inside of the gaff. The Peruvian coin is on the other side of the insert. The Chinese coin is on the other side of the shell.
It doesn’t get any better than this. It’s the perfect set to carry everywhere you go.
Not many of these sets exist!