Sliding racks* adjust to the length of the bed to carry different loads up to 600 pounds *Thule TracRac Base Rails are required (sold separately), providing drill free installation and secure into the truck stake pockets Ideal rack height (18”) allows for easy truck bed access and sits below cab of truck for improved aerodynamics Compatible with retractable tonneau covers (see fit guide) Theft resistant system locks rack to base rail (locking knobs included) WindDiffuser technology disturbs airflow to reduce noise and drag for improved fuel economy Secure different size loads with adjustable aluminum load stops Racks can be easily removed from base rails (sold separately) Easily mount the Thule Xsporter Pro Shift/Mid Accessory Side Bar for additional gear hauling capacity (sold separately) See Thule Buyer's Guide for recommended fits