{TAIL ~ The single crystal blades} are provided with a root portion which contains {HEAD ~ a recess} or cavity which conforms closely to the disk protrusion 
{ TAIL ~ The single crystal blades } are provided with a root portion which contains { HEAD ~ a recess } or cavity which conforms closely to the disk protrusion
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH