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