{HEAD ~ The wafers} are then removed from {TAIL ~ the reactor tube} and further processing is performed upon them 
{ HEAD ~ The wafers } are then removed from { TAIL ~ the reactor tube } and further processing is performed upon them
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH