North Water Barrel CoolerTwo sizes of insulated Barrel Coolers help keep cold things cold on hot days. Each size works on its own, or with its appropriate Blue Barrel in tandem with the TriBags, Barrel Caddy, and Barrel Accessory Roll systems to provide the perfect configurations for before, during, and after your trip. Choose the Large for a 60 L Blue Barrel or Small for a 30 L Blue Barrel. " closed cell foam for insulation. Double walled with roll top closures. Seam taped