{TAIL ~ A vacuum treatment system} has {HEAD ~ an outer housing} which defines a substantially cylindrical inner wall around an axis 
{ TAIL ~ A vacuum treatment system } has { HEAD ~ an outer housing } which defines a substantially cylindrical inner wall around an axis
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH