It was used to bend a 6.35 x 0.8 annealed copper pipe. When loose bending, it bends easily, easily. It bends little by little, moves, bends and moves, and it becomes usage, but it becomes difficult to move when the radius is 10 cm or less. In such a case, push the spring in the direction you want to move while turning the spring in the loosening direction. If you pull it or rotate it in reverse it tightens in reverse and will not move. It is inexpensive, but it fulfilled the function firmly.