Light weight for increased fuel mileage relative to other tonneau covers.. All Galvaneal Sheet Steel.;;;;Superior Construction for added security and durability.;;;;Light weight for increased fuel mileage relative to other tonneau covers.;;;;One of a kind style. Superior Construction for added security and durability. Add a luggage rack reflexxion universal luggage rack for tonneau cover (comes with mounting kit) 2007 silverado 5.5 foot bed to the top of your hard top tonneau cover for extra cargo capacity.