A plurality of {HEAD ~ rectangular notches} 32 extend inwardly from the second edge 20 of {TAIL ~ the partition} 14 
A plurality of { HEAD ~ rectangular notches } 32 extend inwardly from the second edge 20 of { TAIL ~ the partition } 14
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH