The instrument 3 wherein said {HEAD ~ rotator} is configured to be manually actuated by a user of {TAIL ~ said instrument} to change said rotational orientation of said opening 
The instrument 3 wherein said { HEAD ~ rotator } is configured to be manually actuated by a user of { TAIL ~ said instrument } to change said rotational orientation of said opening
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH