In FIG 1 a printing cylinder 1 has two plate locking devices, of which 2 is {HEAD ~ a leading edge locking device} for locking {TAIL ~ a leading edge} of a printing plate, and 3 is a trailing edge plate locking device 
for locking
In FIG 1 a printing cylinder 1 has two plate locking devices , of which 2 is { HEAD ~ a leading edge locking device } for locking { TAIL ~ a leading edge } of a printing plate , and 3 is a trailing edge plate locking device
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH