The hub 8 includes {TAIL ~ a flange} 25 at one end engageable with {HEAD ~ an outer face} 26 of the first hub collar 22 and has an outer male threaded portion 27 at its distal end 
The hub 8 includes { TAIL ~ a flange } 25 at one end engageable with { HEAD ~ an outer face } 26 of the first hub collar 22 and has an outer male threaded portion 27 at its distal end
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH