First of all, {TAIL ~ the pressing roller unit} or {HEAD ~ a plurality} of such units is located at the appropriate location or locations 
First of all , { TAIL ~ the pressing roller unit } or { HEAD ~ a plurality } of such units is located at the appropriate location or locations
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH