A manipulator (1102) comprises a hollow shaft (1108), wires (52, 54, 56) provided on the shaft (1108) and a working unit (1106) disposed on one end of the shaft (1108) and being driven by at least one wire of the wires (52, 54, 56), the working unit (1106) having a tip tool (1118) including a rolling mechanism which rotates about an axis Or directed to a distal end thereof. A tip side surface (1108a) of a proximal end member and a cover (160) of a distal end member are relatively rotated by the rolling mechanism. The cover (160) has a rotation identifier (1208) for indicating a degree of relative rotation of the tip side surface (1108a). The tip side surface (1108a) has an alignment indicator (1210) for indicating an initial position of the cover (160).
