Unlike other silnylon fabrics on the market, our silnylon is made specifically to be both windproof AND waterproof. These fabrics are coated with a silicone layer on each side and are non-breathable. Silnylon is made by impregnating a thin woven nylon fabric with liquid silicone from both sides, making the silnylon very strong for its weight, as well as substantially improving the tear strength of the fabric. Silnylon fabric is perfect for use in the manufacturing of backpacks, tarps and tarp tents, bivy bags, stuff sacks, backpacks, kites, or any gear/project where ultralight, waterproof/windproof fabric is needed. Check out our newest addition, the "Mountain Series" 1.1 oz MTN Silnylon XL. If you're looking for the strongest, lightest, and most waterproof Silnylon on the planet, this fabric is it!