This is a cover for the back of the HicTop Prusa i3 display.
The original file was for the thin controller, 32mm in my case, I've added a 40mm one for the larger types of controller boards
It's available to copy/edit yourself on OnShape as:
Printer:
HicTop Prusa i3
Rafts:
No
Supports:
No
Resolution:
0.15
Infill:
50%
Notes:
I'd recommend PLA with the fan on, otherwise the SD card slot will need some support, plus you'll need to flip it so it prints with the top on the bed.