{TAIL ~ The first and second top shield sublayers} 31 and 32 have {HEAD ~ a uniform thickness} 
{ TAIL ~ The first and second top shield sublayers } 31 and 32 have { HEAD ~ a uniform thickness }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD