{TAIL ~ The assembly} 1, wherein the casing and {HEAD ~ the collars} are made of composite material 
{ TAIL ~ The assembly } 1 , wherein the casing and { HEAD ~ the collars } are made of composite material
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH