If you have any request on the design just ask me.
Here is the explanation of the files names:
Flex: made for elastic filaments like TPU. Tested on TPU.
Rigid: made for rigid (non-elastic) filaments like PLA, ABS, HIPS, etc. The entire model is a little bigger and the holes for the buttons are opened on the front side. Tested only on PLA.
Closed: The traditional mobile phone case design with the hole for the camera and flashligth.
Opened: It is widely opened in the back so that the phone can dissipate the heat easily.
WG: suggested for white and gold models. It's better to print in dark colours to make contrast.
B: suggested for black (dark gray) models. It's better to print with light colored or transparent filaments.
If you set the wall width to one filament line (0.4~0.6mm) and the infill overlap to higher amount (70~100%) you could have a rough wall surface.