panel and provide a receiving area for pallets of various sizes and having depending legs they also serve the dual purpose of stiffening and reinforcing the panel 12 the panel 13 also has a planar portion 30 surrounded by a depending flange 31 which has a horizontally extending footpiece 32 at its lower end the size of the panel 13 is such that when the panel 13 is nested within the panel 12 the footpiece 25 of the panel 12 seats on the footpiece 32 of the panel 13 and the edges of the two footpieces are in the same vertical plane fig6 and 8 the panel 13 has a plurality of parallel raised ridges 34 extending in a front to back direction in addition the panel 13 has a plurality of parallel depressed channels 35 also extending in a front to back direction the tops of the ridges 34 and the bottoms of the channels 35 are flattened both the channels and the ridges are long narrow structures which in the case of the channels extend substantially the full length of the lower panel 13 the ridges 34 are shorter and designed to seat between the front and back recessed wells 21 of the upper panel 12 when the two panels are sandwiched together when the lower panel 31.