PURPOSE: To easily take out an inner member from a container even by an aged person by providing an opening capable of operating one part of the inner member from an outside on an outer member of a closure device, and turning the inner member from the outside using a coin, etc.

CONSTITUTION: When an outer member 16 is turned clockwise, a claw is butted against an engagement part 34 of an inner member 10, and the inner member 10 is turned to be tightened against an adjacent container. By pressing the outer member 16 in the axial direction toward the container, the outer member 16 is moved along the inner member 10, and the claw is pressed against the inner surface of a top part of the outer member 16. When the outer member 16 is turned counterclockwise, an engagement part 36 on a lower side of the top part of the outer member 16 is engaged with an engagement part 34 of the top part of the inner member to turn the inner member 10, for a person difficult to achieve the operation, the inner member 10 can be detached from the container by inserting other operation member such as a coin for an auxiliary means into a groove 26, and directly turning the inner member 10.