The coupling portion and the main cylindrical member have {HEAD ~ a pair} of {TAIL ~ holes} formed to correspond to each other, one of the pair of holes having a tapered surface inclined with respect to the axial direction 
The coupling portion and the main cylindrical member have { HEAD ~ a pair } of { TAIL ~ holes } formed to correspond to each other , one of the pair of holes having a tapered surface inclined with respect to the axial direction
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH