Next-Gen Ultralight Protection for Trail Miles and Travel The Helium UL Jacket is built for fast miles and weather that won’t make up its mind. Ultralight, waterproof, and easy to pack, it moves from trail running, hiking, or peak bagging to travel and daily wear without missing a beat. The next-generation Helium UL Jacket features Toray Dermizax™ 3D 2.75-layer waterproof protection for true ultralight performance, with improved breathability, comfort, and durability. A wire-brim hood, shaped cuffs, and clean bonded edges improve fit and reinforce high-wear areas, while YKK® Aquaguard® zippers and fully seam-taped seams seal out unpredictable weather at a weight that disappears into your pack until you need it.