One or more metal tubes passes through the holes of {HEAD ~ the plates} to position the plates with {TAIL ~ their second portions} forming a substantially continuous sheet 
One or more metal tubes passes through the holes of { HEAD ~ the plates } to position the plates with { TAIL ~ their second portions } forming a substantially continuous sheet
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH