30D Ultra-Sil®
![30D Ultra-Sil®](http://seatosummit.eu/cdn/shop/articles/30D_UltraSil_8422ac6c-568f-4fa7-b821-dc2acf1432b5.png?v=1653006161&width=1200)
An incredibly lightweight yet durable fabric used in a large number of Sea to Summit products. This 30 denier Nylon is made with CORDURA® yarns for strength, woven into a ripstop pattern. Two versions of the fabric are used:
- water-resistant products (such as the Ultra-Sil Stuff Sacks) are siliconized on both sides for ultimate packability
- waterproof products (such as the UltraSil Dry Sack are) siliconized on the outside and PU-coated on the inside to allow seam taping.
Both versions have a hydrostatic head greater than 2000mm – which makes them more than adequately waterproof for the types of environments they are intended for.