Sea to Summit Ultra-SIL View Dry Sack nylon 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 Siliconized fabric for extra strength, durability and a smooth finish for easy packing Polyurethane coated and fully seam sealed for ultimate water-proofness Ultra-Sil30 D siliconized high-tenacity CORDURAnylon fabric for exceptional strength Ultra-Silfabric has a 2,000mm waterhead Hypalonroll top closure does not wick moisture Siliconized fabric for extra strength, durability and a smooth finish for easy packing Polyurethane coated and fully seam sealed for ultimate water-proofness Reinforced stitching for greater seam strength on all stress points Super compact and ultra lightweight Round base design in all sizes Suitable to keep contents dry in any wet situation where the bag is not submerged This product is not intended for boating or marine use