This storage system is designed for complete weatherproof protection of your cargo. The sloped front deflects water and air up and over the bag. Constructed of durable fiberglass reinforced waterproof tarpaulin material that ensures durability and weather resistance. With over 11 cubic feet of extra storage space this is a perfect alternative for thos expensive plastic pods. No drilling required - attaches with heavy duty polypropylene straps to your existing roof rack.