Extang Solid Fold hard folding truck bed cover part # 56651 is one of the best designed, most water tight, most secure, and easiest to install tonneau covers on the market today. The Extang Solid Fold 's tri fold design is three panels that are linked together by a unique hinge system that allows the rear and middle panels to be folded over and stowed with the front 1/3rd of the bed still covered. The Solid Fold panels are two layers of aircraft grade aluminum alloy with a center honeycomb core structure for added strength that is coated with a UV safe textured black finish. The clamps, hinges, and frame all store neatly on the cover so it ships out completely assembled making installation a simple one man job that only takes about 5 minutes. The tailgate has to be lowered to open the cover so if the tailgate is locked the entire bed is locked.