If you are into printing flexible filaments you might like this simple and durable one piece wallet design. It fits around 5 cards, 5 notes and a few coins in its minimal form factor.

It takes advantage of the flexible TPU material with a side squeeze mechanism to create a larger opening to access your stuff [see photo] and when in your pocket the cards and cash stay firmly in place.

We printed this wallet with Black TPU 95A shore hardness [Ultimaker]

To print this design we used an Ultimaker 2+ 3D printer and the print in the photos is printed with a 0.4 mm nozzle. [Because of the thin wall sections we wouldn't recommend using a larger nozzle diameter]

If you haven't printed with flexibles before this may involve a bit of a learning curve, be sure to use the recommended speeds and profiles indicated by the flexible filament you are using.