The super compact and ultralight Sea to Summit 13 Liter Ultra Sil Dry Sack may not be intended for boating or marine use, but it still provides excellent protection from rain and splashes, making it ideal for camping and backpacking. Ultra Sil fabric is made from the lightest and toughest waterproof nylon available, making these stuff sacks 50% lighter than other popular Sea To Summit dry sacks. Super compact and ultra lightweight. Made of Ultra Sil nylon, a polyurethane coated Siliconized Cordura for ultimate waterproofing and maximum durability. Watertight, non wicking Hypalon roll top closure with stiffener at the top for a better seal. Soft and flexible with a slippery finish for easy packing. Nearly transparent for good visibility of contents. All seams are double stitched and tape sealed. Round bottom. Size: 8.5 in. x 21 in. Wt. 1.4 oz.