28 referring now specifically to fig8 the side walls of the collar member 22 are urged towards one another by the application of forces substantially in the directions indicated by the arrows 114 and 116 causing the collar member 22 to assume an oval configuration substantially as shown by the dotted outline 22 39 the saddle member 52 may now be placed in the extended lower looped portion of the collar member 22 as viewed in fig9 and the forces 114 and 116 removed the dotted outline designated by the numeral 118 fig9 illustrates the configuration of the collar member 22 prior to the insertion of the saddle member 52 therewithin while the solid outline indicates the final configuration of the collar member 22 with the saddle member 52 in place as the side walls of the collar member 22 tend to return to their original configuration which is exemplified by the solid outline in fig8 and the dotted outline 118 in fig9 there are generated a pair of opposing forces indicated by the arrows 120 122 fig9 which in turn generate a further force in a direction normal to the force vectors 120 and 122 and indicated by the arrow 124 the force indicated by the arrow 124 tends.