A system to provide ballast weight and to secure accessories on a vehicle load bed includes a plurality of hollow planks placed on the load bed adjacent to each other with end edges of the planks substantially aligned with each other and with side edges of the planks adjacent to each other such that top surfaces of the planks form a substantially flat load surface. At least one plank includes a filling orifice with a removable cap to allow filling with ballast. Recesses at corners of the planks are configured to form a substantially horizontally oriented lobe on each corner of the planks, and adjacent planks are connected at right and left ends thereof by a clip extending into the corresponding recesses of the adjacent planks, and fastened to the lobes on the adjacent planks. At least one clip is fastened to the load bed.