To provide a connecting device capable of being miniaturized without dividing in no use and extended to a prescribed size in use by providing a first hinge for bendably connecting one member to the other member, a fixing member for non-bendably fixing both the members, and a second hinge for bendably connecting both the members to the fixing member.

In a hair dying brush 1, a fixing member bendably connected to a hairdressing member connecting handle member 2 through a second flexible hinge part 6 is pressed to the connecting handle members 2, 3 of a hairdressing auxiliary member, whereby one end and the other end 5a, 5b can be housed respectively in one end and other end housing spaces 7a, 8a. Since the one end and the other end 5a, 5b make contact with both the connecting handle members 2, 3, both the connecting handle members 2, 3 can be non-bendably fixed. The fixing member 5 is separated from both the connecting handle members 2, 3, whereby the one end and the other end 5a, 5b can be separated from the one end and other end housing spaces 7a, 8a, and the connecting handle members 2, 3 bendably connected by a first flexible hinge 4 can be bended.