{HEAD ~ The middle nozzle} provides {TAIL ~ water}, air or other chemicals as coolant to insulate the inner nozzle 
{ HEAD ~ The middle nozzle } provides { TAIL ~ water } , air or other chemicals as coolant to insulate the inner nozzle
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH