A coupling sleeve with a curved rotation prevention protrusion

摘要

A sleeve for coupling a shaft to a club head comprising a bore, an outer wall 3130 and first and second coupling elements 3111 protruding from the outer wall 310 wherein the coupling elements 3111 have an arcuate surface which can combine with a hosel to restrict rotation of the sleeve. The coupling elements 3111 may be curved to have a vertical radius of curvature of at least 10.1mm and a horizontal radius of curvature of between 2.5mm and 5.7mm. A club head with cooperating arcuate surfaces to receive the coupling elements may be provide such that the lie and loft of a club can be adjusted by changing which coupling elements engage which cooperating surfaces. A fastener may be provided including a threaded bore. The arcuate surfaces may be quadric and define parabloid, conical or hyperboloid surfaces.