FIG 3 further illustrates the provision of a notch 90 formed by {TAIL ~ shoulders} on the adjacent facing circumferential ends of {HEAD ~ the segments} 80 
FIG 3 further illustrates the provision of a notch 90 formed by { TAIL ~ shoulders } on the adjacent facing circumferential ends of { HEAD ~ the segments } 80
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH