The PackRight Car Clip Strap Set allows you to use car-top carriers on vehicles without luggage racks. The straps attach to any available ledge on your vehicle’s doorframe that will fit into the 5/8"-wide opening of the "J-hook". Once the straps are tightened over the carrier, the hooks pull into place and your vehicle door closes over the hooks/straps. The Car Clip Strap Set can be used to safely attach any PackRight car-top carrier to your vehicle.