This is a hook for a backpack onto a cubicle wall (wall width is 52mm, I don't think walls are standard, but there are only like 3 different widths)

A few things to note, after I took the picture, I realized the hook was wider than necessary, so the stl is now a bit more narrow. The writing in the picture above isn't actually on it, that was customized later.

Update: This design proved to be a bit weak after a month of use, so I redesigned it to add strength at the weakest areas. It is a bit wider in the bottom hook area, and I removed the slot that was in it as it was causing the failure. (I also made the width a bit smaller since it was overkill before)

Creality

Ender 2

No

Yes

50

supports are required for the inserted piece, but just touching build, and they are minor and super easy to remove.