The taper bit 16 is formed at {HEAD ~ the fore end} of {TAIL ~ the smaller diameter parallel thread part} 15 
The taper bit 16 is formed at { HEAD ~ the fore end } of { TAIL ~ the smaller diameter parallel thread part } 15
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH