Referring to the example of FIG 5, {HEAD ~ the J slot} 70 of the string engaging means 26 are housed in a J slot sleeve 136 which is fastened to {TAIL ~ the upper end} 52 of mandrel 22 
Referring to the example of FIG 5 , { HEAD ~ the J slot } 70 of the string engaging means 26 are housed in a J slot sleeve 136 which is fastened to { TAIL ~ the upper end } 52 of mandrel 22
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH