The plates forming contact surfaces 2 are intermediately supported by the intermediate weir 13 within {HEAD ~ slots} formed in {TAIL ~ the intermediate weir} 
The plates forming contact surfaces 2 are intermediately supported by the intermediate weir 13 within { HEAD ~ slots } formed in { TAIL ~ the intermediate weir }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL