This is a speaker box for a 3.5 inch speaker. This can be used for a wired auxiliary or for a bluetooth. There is a screw and threaded hole to secure the speaker wires or charging cable and 13 mm hole for an on/off switch. The flat panel is to mount any electronics on and screw into place in the box. Infill and wall settings depend on how sturdy you want it. I would recommend a minimum of a three line shell and a 50% cubic infill. For the sturdiest I would go with 2 line walls and a 100% zigzag infill. This will need supports but rafts are up to user.

ELEGOO

ELEGOO NEPTUNE 3

Doesn't Matter

Yes

30% cubic