{HEAD ~ A camera mountable arm} includes a first segment, {TAIL ~ a second segment}, and a third segment 
includes
{ HEAD ~ A camera mountable arm } includes a first segment , { TAIL ~ a second segment } , and a third segment
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH