Front Runner WindCheetah roof racks are all aluminum, fully welded and powder coated in black.They all come standard with a patented slat that accommodates 8MM bolt heads allowing for accessories to be mounted and removed as needed without drilling. Extra legs can also be fitted for better support of heavy loads.Front Runner WindCheetah roof racks are extremely light and strong plus their low profile and lack of sides allows for very little wind resistance and makes them ideal for use with rooftop tents.