Pastamatic Centering Adapter for Winder/driver side.
The winding side of the spool was not centered to the mechanism that helps the windings lay neatly on each other. result was one side of the spool was getting too many windings while the other too little.
this small adapter slots on and is used to shift the spool left or right to help center it more to the winding mechanism.
credits to Pastamatic spool winder: https://makerworld.com/en/models/16606#profileId-15400