Bass guitar tuner ferrule that I designed in Fusion 360. They do not have threads but when tightened (preferably with a socket because a wrench or pliers may damage the plastic) onto the tuner they created threads due to be made out of plastic.
I made this because I ordered a set of bass tuners from china and when I received them they were missing the ferrules, washers, and mounting screws. I contacted the people I bought it from and they sent me a new set and let me keep the original ones. I did not want the tuners to go to waste so I decided to make this so I can use those tuners for a different project.