It also has {HEAD ~ an end bar} of {TAIL ~ hafnium} secured to the bottom plug by a purely mechanical connection 
of
It also has { HEAD ~ an end bar } of { TAIL ~ hafnium } secured to the bottom plug by a purely mechanical connection
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH