This a design that I made because i had a problem that my spools would roll forward when I would try and put them on my shelves. When I installed these, it stopped the rolling of the spools of filament.
I would suggest a higher infill as the part doesn't have a lot, and when I did do a lower infill, it wouldn't be as strong.

V2- Changed how deep the screw holes were because if I would go slightly too far they would crack at that point.