The notches hence cooperate with {TAIL ~ the pins} to serve the above discussed functions of {HEAD ~ the pins} 
The notches hence cooperate with { TAIL ~ the pins } to serve the above discussed functions of { HEAD ~ the pins }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD