The spring 34 may be formed of {HEAD ~ a variety} of {TAIL ~ steel materials} and alloys 
of
The spring 34 may be formed of { HEAD ~ a variety } of { TAIL ~ steel materials } and alloys
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH