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This joint is created to replace the existing joint in case it broke. Design is the same with slight improvement at its original weakest area.
Note: Depends on printers, some filing may be required at the tab clipping in at the side chest. Judging through previous own printout, dimension of the spheres had been increased to cater for printing tolerance. Result in some filling required at the spheres getting it into the tolerances for the ball joint's cup.