Light enough for every climber’s pack, tough enough for the worst conditions. The Alpha SL Jacket provides exceptional durability, breathability, and waterproof protection against the very harshest alpine conditions, while staying so light and packable that carrying it on technical climbs and long mountain days is never a second thought. No excess, just pure function. And as the lightest GORE-TEX PRO shell ever made, it's a new benchmark in alpine minimalism. What's been updated: The Alpha SL Jacket now features GORE-TEX PRO ePE with our propriety Hadron™ face fabric in an ultralight 20D weight, delivering the highest-performing waterproof, breathable protection while remaining free from intentionally added PFAS. The fully adjustable, helmet-compatible StormHood™ offers a precise fit with unobstructed upward and peripheral visibility. The addition of a low-profile RECCO® Reflector improves your searchability in emergency situations.