I needed new leveling knobs / leveling wheels for my Ender 3 pro. Since the original ones were not a very good quality (especially the thread) I decided to print new ones. For the thread I used good quality M4 nuts.
I printed all 4 at once on my Ender 3 pro - no support needed.
update: I have added another wheel / knob with a smaller shaft (10 mm)
update: uploaded another version with nuts on both sides of the shaft...