As illustrated in FIG 3, {HEAD ~ the third roller} 20 has {TAIL ~ a depth T20} which is the same as the depth T22 of the second roller 22 
has
As illustrated in FIG 3 , { HEAD ~ the third roller } 20 has { TAIL ~ a depth T20 } which is the same as the depth T22 of the second roller 22
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH