Features of the Sea to Summit 1.5L Ultra Sil Stuff Sack Water-resistant, bluesign Approved Ultra-Sil 30D nylon fabric with a Non-PFC DWR finish Easy to operate drawcord with capture cord lock Slippery fabric and secure grab handle at base for effortless sliding in and out of packs Proprietary Ultra-Sil fabric employs Corudra High-tenacity nylon yarn for increased strength and abrasion resistance Ultra-Sil Dry Sacks, the 30D High-tenacity nylon outer face is impregnated with silicone and a Polyurethane (PU) coating is applied on the inside Water resistance of over 2,000mm Silicone outer face sheds water exceptionally well and creates a slippery surface for easy packing PU coating on the inside improves the waterhead rating and allows for sealing of the seams.