The cannula or {TAIL ~ probe tip} 14 is {HEAD ~ a rigid, tubular sleeve} preferably constructed of surgical steel 
The cannula or { TAIL ~ probe tip } 14 is { HEAD ~ a rigid , tubular sleeve } preferably constructed of surgical steel
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH