The Rightline Gear Cargo Saddlebag is a patented cargo carrier that attaches to the back of your vehicle, WITH or WITHOUT a roof rack. The rear vehicle location allows for easy loading and access to your gear, and because it produces no aerodynamic drag, it saves $$$ at the gas pump. The bag is made from UV protected PVC Semi-Coated Mesh XT and Hydrotuff for maximum durability. The materials are sewn together for strength and then welded along the stitching to make the seam waterproof. The bottom pole frame provides structure and rigidity for the bag. Add the Saddlebag Car Clips (sold separately) to attach the Saddlebag to the rear hatch door on vehicles without a roof rack.