Premium aerodynamic load bars for an exceptionally quiet ride and easy installation of accessories. 2-pack. Load bar for Thule Evo roof rack system WindDiffuser technology disturbs airflow to reduce noise and drag for improved fuel economy TrailEdge design reduces aerodynamic drag by allowing clean air separation from bar SmartSlides slidable length scale doubles as an under-bar aerodynamic cover, providing quick, no-hassle rack installation SwingBlade end cap pivots open to allow full access to the T-slot for easy accessory installs Upper T-track with QuickAccess interface allows smooth installation and removal of accessories BoxBeam internal structure creates an exceptionally strong load bar Check the Thule Buyer's Guide to find out which roof rack fits your car