This is a case for a single Micro SD card. It will protect your card on your travels.
I made this with my Robo 3d R1 printer.
Layer height: 0.2mm
I laid the parts out so I wouldn't require any support material (no overhangs).
I don't know how this will turn out in other printers since this is a press fit and I'm dimensioning this to my printer.
I designed it to fit without needing to sand or file anything. But if you want the tray completely flush with the case like in the pictures you'll need to file a little bit from the bottom of the tray. It's not necessary but I think it looks better.