To provide a hollowing out tool that has excellent usability.SOLUTION: A hollowing out tool includes a connection part (2), an arm part (3) connected to the connection part (2) and an action part (4) connected from the arm part (3).SELECTED DRAWING: Figure 1【課題】使い勝手が良い刳り貫き器具を提供する。【解決手段】接続部(2)と、接続部(2)に接続するアーム部(3)と、アーム部(3)から接続している作用部(4)とを備える刳り貫き器具。【選択図】図1