Increase Storage Space-This large 18.5 Cubic Feet capacity car roof storage bag makes you never run out of space for carrying all you need on your trip or adventure. Constructed with 3 Layers Underwater Diving Material & Completed Weatherproof Zipper is guaranteed to protect your luggage & cargo from rain, snow, wind, and debris. Works on all car with or without racks 100% Waterproof Sealing Design- Welded seams with Penetration resistant coating and the velcro flap that covers the zipper help to against the strong wind?heavy rain or snow during driving. Clinging to the bag to keep water out. Keep Your Possessions Stay Dry with ROYI cargo box.Our car top carrier is strong, durable and desgined to last Easy To Install-This car rooftop luggage carrier couldn't be easier to install. Provide 2 pairs of Strong,wide heavy duty straps to let our cargo carrier stay firmly on your car rack or car inner handrail. Ensure that everything stays in place even on rough and bumpy road during driving.When not in use you can fold and store the bag compactly and easily inside the included storage bag Military Grade Materials-This premium quality bag is made of military grade materials with waterproof dual seam technology. Pack all you want with the confidence that your luggage will stay safe and resistant to all types of weather during your travels Worry-free Purchase-Rest assured that your ROYI product for quality issue is backed by 3 year warranty and lifetime technical support. If for any reason you're not completely satisfied with your cargo bag, you can feel free to contact us for a full refund using our risk-free money back guarantee