The discs may include inwardly directed notches formed in their outer perimeter, with {HEAD ~ the notches} cooperating with an interior wall of {TAIL ~ the housing} to cut tissue specimens 
The discs may include inwardly directed notches formed in their outer perimeter , with { HEAD ~ the notches } cooperating with an interior wall of { TAIL ~ the housing } to cut tissue specimens
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH