This is a case for the Raspberry PI Zero 2w case for mounting it to the back of a flashforge creator pro. It may work for other use cases, but it was designed for that purpose, and the bracket is meant to fit the creator pro, and the mounting holes are meant for filament runout sensors to mount on either side.
To assemble you print the top and bottom, and then you glue the bracket onto the side, which will then slide into the back of the printer.
The author marked this model as their own original creation.