Abstract: A reusable container closure which telescopes over the open top or bottom of the container. The closure side walls have locking flaps at each end. The closure end walls wrap around the locking flaps to hold the closure side and end walls in upright position. Temporary locking elements bear against the inner face of the inner end wall and hold the end and side walls in position. The temporary locking elements are formed from and hinged to at least one of the central or side panels and are bent from the planes of these panels to hold the side and end panels in place. When the closure is telescoped over the container, the container pushes the locking elements back into the plane of the panels and the container now holds the side and end panels in place. When the closure is removed the side and end panels are no longer held in place and may be flattened for reuse easily.