Abstract: A universal joint 10 for the extension of billiard cues. The joint comprises a joint element 12 generally tubular and adapted to hold at one end the front end of an extension and to receive at the other end the butt end of a billiard cue, and a generally tubular tightening element 14 adapted to lock the cue inside the joint element 12. The joint 10' is operative irrespective of the outer diameter of the butt terminal part of the cue received therein, by the combined action of slits 42, tapered portions 28, 38, 40 and resilience of the material of which the joint element 12 is made.