Abstract: An improved hard sided cargo container having a top, bottom and four vertical walls, two opposing walls of said container being pliant to permit incremental vertical expansion or contraction of said walls responsive to loads on the floor of the container.

Abstract: A core having a repetitive pattern for ribbing comprising triangles and hexagons where each side of any given hexagon is extended pinwheel fashion toward the appropriate side extensions of each of the six adjoining hexagons, all of the hexagons having sides extending to form pinwheels having the same sense, i.e., clockwise or counterclockwise. The triangles are defined by the extensions and are located between the hexagons. Panels using this core are stiff about all axes and do not have an angle of inherent weakness. The core may be stamped, rolled or vacuum-formed out of many materials including paper, cardboard, sheets of various metals and reinforced or thermosetting plastic.