This is a 3 slot SD card holder that's the dimensions of a credit card, just thicker. If you were really determined, you could make it slightly thinner, as is it's about 7mm thick. It has the American flag on it, because America, but you can replace that. There's also a hole so you can attach it to things, I don't recommend having it outside of a bag, just in case if it slips apart, my camera bag has a ring inside a pocket, so it works there.

This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/7swzTAR8FaY