A clip attaching structure includes a clip supporting portion which protrudes on an outer circumferential surface of a main body, a clip, and a coil spring. The clip is configured to be rotatable with respect to a fulcrum at which the clip is engaged with the clip supporting portion. The convex portion is inserted into an inside of one end portion of the coil spring, and the other end portion of the coil spring abuts against the outer circumferential surface of the main body. A base portion of the convex portion has an outer diameter greater than an inner diameter of the coil spring, and a tip end portion of the convex portion has an outer diameter smaller than the inner diameter of the coil spring.