{HEAD ~ The second material} for the outer core, preferably polyurethane foam, consists of 100 parts of a resin mixture, a blowing agent, and {TAIL ~ either 51 or 60 parts} isocyanate 
{ HEAD ~ The second material } for the outer core , preferably polyurethane foam , consists of 100 parts of a resin mixture , a blowing agent , and { TAIL ~ either 51 or 60 parts } isocyanate
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH