Abstract: A sandwich panel multi-sided structure mountable on a vehicle body, as a pick-up truck or trailer. The structure is formed from a single flat sandwich panel comprising a bendable sheet metal facing and a rigid plywood facing bonded to opposite sides of a plastic foam core. The core is a compressible expanded polystyrene foam. The panel is provided with spaced pairs of transverse grooves extended through the rigid plywood facing toward the bendable metal facing. The grooves are along the corner sections and divide the panel into a roof section and opposite side sections. The side sections have openings for receiving window structures. The structure is formed by bending the sheet metal facing and compressing the core along the corner sections to form a roof converging outwardly and downwardly from a longitudinal ridge and upright side walls. The back of the pick-up cover is closed with an end wall having a door.