{HEAD ~ a rod} formed of {TAIL ~ an alkaline metal alloy} tempered to have a tensile strength of at least about 600 psi 
formed of
{ HEAD ~ a rod } formed of { TAIL ~ an alkaline metal alloy } tempered to have a tensile strength of at least about 600 psi
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH