Transistors 51 and 52 are for transferring {HEAD ~ voltage} to {TAIL ~ the selecting gate lines} SGDI 
Transistors 51 and 52 are for transferring { HEAD ~ voltage } to { TAIL ~ the selecting gate lines } SGDI
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH