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