The body of energy absorbing material may optionally be subjected to {HEAD ~ approximately hydrostatic pressure} preferably exceeding {TAIL ~ the shear yield stress} of the energy absorbing material 
preferably exceeding
The body of energy absorbing material may optionally be subjected to { HEAD ~ approximately hydrostatic pressure } preferably exceeding { TAIL ~ the shear yield stress } of the energy absorbing material
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH