The Patagonia Storm Shift Jacket is built around a GORE-TEX ePE 2-layer membrane, a next-generation construction that replaces the traditional fluorinated ePTFE with an expanded polyethylene core, delivering the same waterproof-breathable performance without the persistent chemistry. The face fabric and lining are both 100% recycled polyester, with a recycled polyester zigzag fleece lining that adds warmth and next-to-skin texture without bulk. On a full storm day, the 2-layer construction keeps the shell flexible and packable while the membrane and fleece lining work together to manage moisture from both sides. What Our Gearhead(R) Experts Are Saying:"When the storm rolls in mid-run and the visibility drops to nothing, the helmet-compatible hood cinches down without a fight, the adjustable powder skirt seals out the slough, and the forearm pocket keeps a lift ticket or trail map exactly where I need it. The RECCO reflector is the detail I hope I never need but wouldn't ski without."