The cover has {HEAD ~ a longitudinal extended V} shaped {TAIL ~ protuberance} along a face of the cover which engages the base member 
The cover has { HEAD ~ a longitudinal extended V } shaped { TAIL ~ protuberance } along a face of the cover which engages the base member
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH