The term structural foam refers to {HEAD ~ a body} with {TAIL ~ a low density cellular core} which has a solid integral skin 
with
The term structural foam refers to { HEAD ~ a body } with { TAIL ~ a low density cellular core } which has a solid integral skin
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH