To provide a stick having an exchangeable configuration, especially, simple structure and small radial dimension.

The lengthwise segment of a rotary sleeve 2 away from a top end at least is surrounded with a main body 1 of stick, at least one operation window is provided on the peripheral wall of the main body 1 of stick surrounding the rotary sleeve 2 by notching, the rear end part of a core material 3 is inserted into the force segment of a core material driving part 4 formed as a tube segment-shaped core material holding part 10 so as to disable turn and axial move, and further, this core material holding part 10 is cooperated with the inner peripheral surface of the rotary sleeve 2 as an axial guide on the outer peripheral surface.