Thule SquareBar Evo square bars are made of corrosion resistant, galvanized steel and are coated in black polymer to provide extra grip for your cargo. This roof rack has a classic design which also makes it compatible with a wide range of cargo carriers and rooftop accessories. Thule constantly aims to stay one step ahead of the curve - that's why roof rack systems like this one can take a heavier load than most roof racks on the market.