The Model 975401-3-01 Shelf Unit Mounting Kit bolts to reinforced sections of the van wall through existing holes provided by Chevrolet in the low roof Express 135in wheelbase van for faster, easier and more secure shelving installation. Extruded aluminum upper mounting rail distributes load of shelf units and contents and provides flexible mounting locations during installation. No floor mounted rail to interfere with wide or bulky items under the bottom shelf.