Patent ID: 8795159

Claim:
An endoscope comprising: an insertion main body which is extended along a longitudinal axis, and which is configured to be inserted into a lumen, the insertion main body comprising: a first tubular portion; and a second tubular portion positioned distally which is provided to the first tubular portion, the second tubular portion having a flexibility more flexible than a flexibility of the first tubular portion, the second tubular portion including a passive bending portion configured to passively bend when external force acts thereon; an attachment unit through which the insertion main body is inserted, the attachment unit having a fin portion spirally extending along the longitudinal axis, the attachment unit being attached to the insertion main body in a state that a rotation of the attachment unit about the longitudinal axis with respect to the insertion main body is controllable; and a connecting mouth ring which connects connect the first tubular portion to the second tubular portion at a transition between the first tubular portion and the second tubular portion, an outer peripheral direction side of the connecting mouth ring being rotatably connected to a proximal end portion of the attachment unit such that a proximal end of the attachment unit is rotatably attached to the connecting mouth ring at the transition between the first tubular portion and the second tubular portion wherein in a state that substantially all portions of the attachment unit extend distally from the transition.