A hollow plastic dilator 60 is then passed through {HEAD ~ passage} 11 of {TAIL ~ the cannula housing} and is slid over guide 61 
A hollow plastic dilator 60 is then passed through { HEAD ~ passage } 11 of { TAIL ~ the cannula housing } and is slid over guide 61
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH