Adds an Apple AirTag and space for cash, without adding much in thickness (4mm for the AirTag, nothing for the cash).

This remix

•  adds space for an AirTag on the top plate,
• uses some of the thickness of the bottom plate to add space to carry cash. 

Beware: printing the bottom with the cash pocket includes 45mm bridging extrusions, so use a well-tuned printer and material that bridges well (e.g. PLA).

There are three versions, 

1. A Curved Wallet version which looks a bit more streamlined,
2. one for the Modular Wallet, 
3. one for the Popup Wallet which has slightly larger sides. The pictures show what happens when you print the Modular Wallet version and put it on a middle piece of the Popup one.