The height of {HEAD ~ thread crest} of {TAIL ~ the smaller diameter parallel thread part} 15 is as small as about 0.1 mm 
of
The height of { HEAD ~ thread crest } of { TAIL ~ the smaller diameter parallel thread part } 15 is as small as about 0.1 mm
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH