The Car Clips allow any Rightline Car Top Carrier to be used on vehicles WITHOUT a roof rack. Add the clips to the ends of the standard straps included with each carrier and attach them to an available ledge along the vehicle's door frame. Once the straps are tightened over the roof cargo carrier, the hooks pull into place and the vehicle's door closes over the hooks/straps. The Car Clips can be used with the Rightline Gear Sport, Edge, and Ace Car Top Carriers (Note: The Car Clips are included with the Sport Jr Car Top Carrier). Don't let the lack of a roof rack keep you from carrying your extra gear.