The Flea-Scope is a really neat $18 USB oscilloscope. You can find the documentation here:
https://rtestardi.github.io/usbte/flea-scope.pdf
I purchased one to play around with, and found myself wanting a simple case to keep from accidentally damaging the electronics.
I soldered some headers onto the board for the inputs/outputs that I needed, and left openings in the case to easily access these headers.
I used 4 M3 x 12mm hex socket screws with nuts to attach the top.
The model has a very thin layer covering each of the screw holes. This is on purpose and meant to be a 1 layer thick bridging, in place of having to print with supports. I found this easier to handle than dealing with fussy supports. Just use a screwdriver to poke through that layer.
The author marked this model as their own original creation.