Roof Box storage Available here. Though car designers take great care to anticipate and accommodate the needs of their customers, car owners sometimes find that they do not have enough space to store or transport the items that they need. Roof box storage provides that additional space. These storage options employ a combination of rails, racks, bags and boxes that allow drivers to store and haul various items. Size, shape, material used and the type of car to which the box will be affixed are some of the factors that need to be taken into consideration when selecting the best roof box storage option to meet your needs.