i like your design. Is it water proof?
Your design inspired an idea for a design.. I was thinking of just creating a micro sd chip holder which is same dimentions as the screw top of standard water and soda bottles.. then i just have to creat the bottom mount.. and re-use bottle caps instead of printing them.
here is a design i created to hold 3 micro sd chips in wallet. http://www.thingiverse.com/thing:1748452