A cylindrical member 20, a protruding portion 60 protruding from the inner periphery on the distal end side of the cylindrical member 20 and having a wire hole 60 h, a maximum outer diameter portion 41 u formed at the distal end portion, and a wire hole 60 h And the maximum outer diameter portion 41 u is engaged with at least a part of the front end face 60 s of the protruding portion 60 and the inner side in the radial direction K of the maximum outer diameter portion 41 u engaged with the protruding portion 60 And a regulating portion 60a for restricting the movement of the regulating portion 60a to the regulating portion 60a.円筒部材20と、円筒部材20の先端側における内周に突設されるとともに、ワイヤ孔60hが形成された突起部60と、先端部に最大外径部41uが形成されるとともに、ワイヤ孔60hに挿通されて最大外径部41uが突起部60の先端面60sの少なくとも一部に係止される牽引ワイヤ40uと、突起部60に係止された最大外径部41uの径方向Kにおける内側への移動を規制する規制部60aとを具備する。
