{HEAD ~ a pair} of {TAIL ~ flow systems}, each said flow system being disposed for a flow of fluid there through 
of
{ HEAD ~ a pair } of { TAIL ~ flow systems } , each said flow system being disposed for a flow of fluid there through
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH