This iphone 8 / SE (2nd and 3rd gen) case can be customised to fit you logo in the back, to do so, I have included the “PETG_insert_blank” part in many formats so that you can edit it and punch out your logo (alternatively you could also print it out blank and manually carve out your logo). This part should be printed in PETG (or a similar material, PLA might be too brittle but other materials will work). 

The rest of the parts should be printed in TPU (or another flexible filament). 

The case should be quite tight to make sure the phone cannot slip out, to ensure the right fit, you might have to use your slicer to compensate for any imprecision in your printer (XY size compensation).

Since supports do not work with TPU, you will have to print it without supports and then remove the overhanging strings after the print is finished (I used tweezers, pliers and a razor blade to do so).