Official Gazette of the United States Patent and Trademark Office:

Tonneau cover that gives complete access to bed AND works with a tonneau cover with t slot Product Information · Engineered to fit your vehicle · Tonneau cover shields the cargo in your truck bed · Patented vinyl-over-aluminum construction for maximum tonneau cover with t slot cover by combining the Trax Rail System with the t-slot accessories Product Features Low Profile Design; Increased Cargo Capacity Above and Below the Cover

เล่นเกม slot pg T-slot is great stuff, it gives you the ability to mount things literally anywhere along the rail with out having to drill any holes The last