PROBLEM TO BE SOLVED: To provide a fall-off preventive device which is easy to be attached to a bolt. SOLUTION: A fall prevention tool 1 includes a first coil spring portion 2, a second coil spring portion 3, a first arm portion 4, and a second arm portion 5. The first coil spring portion 2 has a wound first coil wire 2A, and the second coil spring portion 3 has a second coil wire wound around the first central axis 7. Has 3A. A first wire 9 connecting one end of the second coil wire 3A and the first central axis 7, and a second wire connecting the other end of the second coil wire 3A and the first central axis 7. The central angle 12 with 10 is 110 °. The first connection point 13 between one end of the second coil wire 3A and the third coil wire 4A, and the second end of the second coil wire 3A and the fourth coil wire 5A. The connection point 14 intersects with a virtual substantially circular body 6 having a radius larger than the winding radius of the second coil spring portion 3 about the second central axis 8 extending substantially parallel to the first central axis 7. doing. [Selection diagram] Fig. 2
展开▼
