It does not hold much, but it hides it very well. Crafted with a secret interior compartment. During the Cold War, spies developed and used these. Now you can too, what you have to hide is now your business. I’m not going to leave things here, From what I have found the coin is not perfect but it’s a start. As the video shows below with a bit of finagling you can make a mini SSD card fit.
While I was looking around for other spy stuff, I found this:
Now I have not ordered it or used it, but It looks like something I might one day, It looks handy to have around. You can find other higher end Depstech products here.