Further, the annular protrusion second end can have {HEAD ~ a series} of external threads on {TAIL ~ its outer surface} for threaded engagement with a series of internal threads of a nut 
Further , the annular protrusion second end can have { HEAD ~ a series } of external threads on { TAIL ~ its outer surface } for threaded engagement with a series of internal threads of a nut
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH