The first tubular member 21 has {HEAD ~ a free end} to which {TAIL ~ an end connector} 22 is mounted 
The first tubular member 21 has { HEAD ~ a free end } to which { TAIL ~ an end connector } 22 is mounted
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH