Ender3 Level screw stop

This is a crude little stopper to ensure the levelling screws don't move during a print. I own a Ender3 S1 and realise that the bed levelling screws kept moving and eventually fell off on long duration prints. This caused failed prints. The purpose of this stopper is to lock the levelling screws in place and preserve the levelling done.

Its a bit tight to fit once perfectly level. So to fit, after levelling slightly turn it in the opposite direction to fit and then let the stopper touch the black plate below the bed. that's all.