A hook for carrying a sling over your backpack strap.

I made models for both right side and left side -carrying.
The only difference is that the left side is a mirrored version of the right side.

I recommend printing the hook on its side without support.
You might need a brim depending on your bed adhesion.
I printed mine with 100% perimeters.
100% perimeters should be better then 100% infill as it should be able to flex more.