Load bars, when used with base rack towers and feet create crossbars on a vehicle roof. Load bars come in different lengths depending on the vehicle size. Load bars also come in different shapes. Some loadbars, like Thule AeroBlade provide increased fuel efficiency, a quieter ride, and increase strength through an aerodynamic design. Load bars, sometimes referred to as crossbars, create the mounting point for the attachment of additional accessories like bike racks, ski racks, boat racks, and cargo racks.