To improve durability and the life of a component by regulating the relative rotation of a rod in relation to a tube.

A guide cylinder 21 in which a hexagonal slide hole 21A is formed on the inner peripheral side is fixed in a strut 2 by fixing pins 24. A guide cylinder 26 in which a hexagonal slide hole 26A is formed on the inner peripheral side is fixed in the strut 2 by fixing pins 29 in a state where it is rotated to the position different from that of the guide cylinder 21. The rotation of a square rod 4 in the strut 2 in one direction is regulated by the guide cylinder 21, and the rotation in the reverse direction is regulated by the guide cylinder 26.