a claw configured to be pushed by a striker and rotated in a fastening direction;

a pawl member configured to contact and interlock the claw and configured to rotate with the claw, such that the claw engages at a half-lock point corresponding to a middle portion of a rotation range of the claw and at a full-lock point corresponding to an end portion of the rotation range, thereby limiting rotation of the claw in an unfastening direction; and

a full-lock detection switch configured not to be manipulated at the half-lock point and configured to be manipulated at the full-lock point by the claw and the pawl member, thereby detecting a state in which the claw is fully fastened to the striker;

wherein the claw has a sub-manipulation portion, the pawl member has a main manipulation portion, and the full-lock detection switch is positioned on a path of rotation of the sub-manipulation portion and on a path of rotation of the main manipulation portion such that, at the full-lock point, the sub-manipulation portion and the main manipulation portion are successively pressed against the full-lock detection switch; and

wherein the full-lock detection switch has a switch button having a free end configured to hinge-rotate around a fixed end, the sub-manipulation portion rotates at the full-lock point and first presses the switch button such that the free end of the switch button is positioned within the path of rotation of the main manipulation portion, and the main manipulation portion rotates to the full-lock point and then presses the free end of the switch button such that the full-lock detection switch is manipulated.