To allow the force to be applied by wind to escape safely and effectively with a simple structure by turning or rotating signboards without countering the wind when hanging rods are passed through annular members and the signboard are fanned by the wind.

Signboard bodies 10 which are mounted at the hanging rods S by anchoring the annular members 20 to the hanging rods S are hung turnably or rotatably around the axis of the hanging rods S. Consequently, the signboards D turn without countering the wind when the signboards D are fanned by the wind. As a result, the force acting on the mounting parts of the hanging rods S supporting the signboards D and a post P when the signboards D are fanned by the wind is minimized. The stable holding of the erecting state of the post P is made possible and the erecting and supporting of the post P are assured by a relatively simple technique.