Patent attributes
A first side wall structure and a second side wall structure each have a plurality of first shelf supporting surfaces and a plurality of first shelf guiding surfaces aligned with one another. The plurality of first shelf supporting surfaces defines a first retention location and a second retention location, and the plurality of first shelf guiding surfaces defines a first movement path extending horizontally between the first retention location and the second retention location. A first shelf moves from the first retention location to the second retention location along the first movement path. The first shelf is a first distance above a vehicle floor in the first retention location, and a second distance above the vehicle floor in the second retention location, the second distance greater than the first distance. In the first movement path the first shelf is inclined contacting the first shelf guiding surfaces.