Fully printed lock nut for bed leveling of the Ender 3 (Im using an ender 3 max). Thread is M4x0.7 which seems to be standard on the ender 3's and should work fine on the other models. I used PETG for sturdiness and they screw on nice and hold the adjustment handles in place. I made the thread 0.1mm larger than standard m4x0.7 to allow for easy screw on without manipulating the bolt and adjustment handle. It is knurled for ease of use.

2/13/23 EDIT: Note: Due to the differences in printers, nozzles, etc the thread may print smaller than desired. If this occurs when you go to tighten it, it will actually loosen your adjustment wheel at the same time. My suggestion would be to slightly increase the model scale in your slicer, or vice versa if it seems too loose.