a pivot support having a pivot axis longitudinally oriented with {HEAD ~ respect} to {TAIL ~ the frame} 
a pivot support having a pivot axis longitudinally oriented with { HEAD ~ respect } to { TAIL ~ the frame }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL