Although not 100% waterproof, the Thule 869 Interstate Roof bag
is Thule's most weather resistant cargo bag yet thanks to double-coated TPE laminate material that is IP-X3 test certified for water resistance, as well as a coated, 3-sided zipper with a large storm flap. This high degree of weather resistance means the Interstate cargo bag will offer the best protection of your gear against rain, sleet, and snow while you head down the road on your adventures. But as with all roof bags that use zippers for convenient loading and unloading of gear (as opposed to less convenient roll-top enclosures), water will eventually find its way inside if the bag is subjected to a long, heavy downpour, so we recommend placing all contents in plastic bags for total waterproof protection if bad weather is threatening. An affordable alternative to a cargo box and easier to install and remove, the Thule 869 Interstate cargo bag offers 16 cubic feet of storage space and can be rolled up and stuffed into the provided convenient storage bag when not in use.