This is like jpcw's SD Card Holder, but on my TOM/Mk7 I needed the slots a little looser. So this looks a lot like his, but is parameterizable.There are several parameters. The main one is for the number of slots. You can also adjust the size of the slots, if you want a tighter or looser fit. (You can also adjust other aspects, like the angle that the top rises from front to back or the car separation distance, if you're a control freak.)You can print the 6 slot stl file that's here, or run scad and change the number of slots.