Ultra-Sil 30 D siliconized high-tenacity CORDURA nylon fabric for exceptional strength. Ultra-Sil fabric has a 2,000mm waterhead * Hypalon roll top closure does not wick moisture. Suitable to keep contents dry in any wet situation where the bag is not submerged * Polyurethane coated and fully seam sealed for ultimate water-proofness. Reinforced stitching for greater seam strength on all stress points * Siliconized fabric for extra strength, durability and a smooth finish for easy packing. Super compact and ultra lightweight. Round base design in all sizes