?Waterproof & Long-Last? 2 kinds of protective measures,the roof rack bag made by the 500D folder grid after high-frequency pressing from refining into a dense and compact surface, more durable and waterproof, coupled with invisible zipper well-designed magic stickers,protecting your luggage against rain, grit, snow, wind and sun. ?Diverse and Easy Installation? Heavy Duty Straps can be easily attached to rack or side rails or cross bars Rails or not.Don't worry about rack issues. The strap can be secured from the top of the bag through the inside of the car and can also be protected from theft. ?Increases Space?15 cubic feet and 39x35.5x16.5in large capacity top bag, convenient for managing and storing your luggage,increasing vehicle cargo space on all standard vehicles,enjoy a comfortable and pleasant travel! ?Strap's Security Designed?Equipped with a metal buckle on the strap to solve the problem of moving back and forth during driving?making you feel more comfortable when driving.In addition, the straps pass through the car door and is installed inside the car to prevent theft. ?1 YEAR WARRANTY? AUPERTO is committed to provide Prompt and Excellent After-sales Service, have any questions, feel free to message us, 100% service and 100% guarantee.