Abstract: A pair of upstanding elongated side rails are provided and interconnected by a plurality of vertically spaced horizontal elongated rungs extending therebetween and pivotally attached at their opposite ends to the corresponding side rails whereby a foldable parallelogram construction is provided. One of the side rails includes anchor structure for anchoring the one side rail in an upright position relative to a suitable support structure and the assembly is foldable between a first closed position with the side rails closely adjacent each other and the rungs generally paralleling the side rails and a second open position with the side rails spaced apart and the rungs generally horizontally disposed.