Retention channel 915 extends substantially {TAIL ~ the entire length} along each edge of {HEAD ~ each part} receiving area 910 
Retention channel 915 extends substantially { TAIL ~ the entire length } along each edge of { HEAD ~ each part } receiving area 910
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH