The cutter of {TAIL ~ the present invention} is connected to the rotary unit and adapted to contact {HEAD ~ the formations} 
The cutter of { TAIL ~ the present invention } is connected to the rotary unit and adapted to contact { HEAD ~ the formations }
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD