A rotatable locking member for locking an aircraft wing with a movable wing tip device. The rotatable locking member including a U-shaped receiving portion arranged such that in an unlocked position the locking pin may be moved into and out of the U-shaped receiving portion, and in a locked position the locking pin is not able to be moved out of the U-shaped receiving portion, and the rotatable locking member is configured to be moved between the unlocked and locked position by rotational movement around the longitudinal central axis of the locking pin.