{HEAD ~ The preheat module} has {TAIL ~ a vertically moveable rack} and is loaded with various sized batches of wafers with no vacant positions between them 
has
{ HEAD ~ The preheat module } has { TAIL ~ a vertically moveable rack } and is loaded with various sized batches of wafers with no vacant positions between them
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH