This simple, but highly effective piece of gear will make life much easier. It removes the potential for your tie down straps to slip off the end of your roof rack bar. It is especially useful for those using wider than average roof bars.
Installation is easy. They simply slide into the channel on the underside of the Vortex bar. You can then run your tie down strap through it and your load is secure.
These come in a pack of two, and include fastening hardware and a tool to tighten the screws.