{TAIL ~ Each roller assembly} 43 comprises {HEAD ~ an upper roller} 45 and a lower roller 46, with a power source 44 for rotating the upper rollers 45 
{ TAIL ~ Each roller assembly } 43 comprises { HEAD ~ an upper roller } 45 and a lower roller 46 , with a power source 44 for rotating the upper rollers 45
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH