A fixed bracket is mounted to the bottom of the spindle, and {HEAD ~ an adjustable bracket} is mounted about {TAIL ~ the adjustable collar} 
A fixed bracket is mounted to the bottom of the spindle , and { HEAD ~ an adjustable bracket } is mounted about { TAIL ~ the adjustable collar }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL