Highland 15 cubic feet KarPak roof top cargo bag now includes a convenient storage sack to store and protect the bag when not in use. The Highland KarPak utilizes sonically welded seams instead of sewn seams and waterproof material to significantly reduce the chance moisture might migrate into the bag during use. Highland"s KarPak utilizes a rain flap over the zipper closure to further protect cargo from moisture and dust. The KarPak soft sided car top cargo bag is a rugged performer and a great value.