To easily rotate a thumbscrew 5 screwed onto a long size bolt 2.

When rotating the thumbscrew 5, the long size bolt 2 is inserted into a hole 12 of a body 14 and a locking part 16 formed at an end of the body 14 is locked on an outside face of the thumbscrew 5. A general tool 28 such as a wrench with a handle is connected to an input part 18 formed at the other end of the body 14 to rotate the body 14. As a result, the locking part 16 is rotated together with the body 14 and rotational force is transmitted from the locking part 16 to the thumbscrew 5.