{HEAD ~ a) an elastic support} exhibiting {TAIL ~ a resilience} of at least 80%; and 
exhibiting
{ HEAD ~ a ) an elastic support } exhibiting { TAIL ~ a resilience } of at least 80 % ; and
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH