see fig1 having beveled edge or lip 42 retaining ring 36 functions to impart the joint clamping forces from carriage 20 through the hooks 28 to the back side of lip 42 of connecting member 40 see fig5 in addition retaining ring 36 resists and counters the radial force component or stresses acting on retaining collars 26 i e potential energy of hooks 28 due to force exerted through pins 32 without retaining ring 36 forward end 22 would tend to 34 bow out 34 the horse shoe shape of hooks 28 cause them to act as stiff spring elements when loaded thereby helping to accommodate machining tolerances and provide uniform loading around the back of lip 42 opposite forward end 22 of carriage 20 is beveled or beveling skirt end 44 this terminus or end 44 defines a cylindrical ring of spaced locking tabs 46 and a spirally grooved inner surface 48 all of which further define an opening 64 for receipt of translating mandrel 50 axial grooves 78 see fig6 cutting across the spiral grooves 48 are also provided along the inner surface of end 42 to permit receipt of the tubular member 70 as more fully described below referring again to fig1 and 2 mandrel 50 defines a hollow tubular body 52 including a crenelated crown 54 having locking fingers 56 and base 58 spiral grooves 60 are formed within outer surface 62 of body 52 and interact with grooved inner surface 48 of skirt end 42 on carriage 20 as explained more fully below as noted mandrel 50 defines a hollow tubular body 52 for receiving tubular member 70 which is provided with annular shoulder or rim 72 annular.