{HEAD ~ The inner cylindrical member} 40 has an outer shape and {TAIL ~ a cross section}, as shown in FIGS 3A and 3B. A pair of housing portions 40a for housing the rear cylindrical members 4 are juxtaposed 
{ HEAD ~ The inner cylindrical member } 40 has an outer shape and { TAIL ~ a cross section } , as shown in FIGS 3A and 3B. A pair of housing portions 40a for housing the rear cylindrical members 4 are juxtaposed
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH OTH OTH OTH TAIL TAIL 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