Extending inwardly from {HEAD ~ the first edge} 18 are a plurality of spaced first slots 26 extending inwardly from {TAIL ~ the first edge} 18  
Extending inwardly from { HEAD ~ the first edge } 18 are a plurality of spaced first slots 26 extending inwardly from { TAIL ~ the first edge } 18
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH