In an embodiment, the apparatus can be used for mounting an arm on {HEAD ~ a bearing} to form {TAIL ~ a pivot} 
to form
In an embodiment , the apparatus can be used for mounting an arm on { HEAD ~ a bearing } to form { TAIL ~ a pivot }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL