What Our Gearhead(R) Experts Are Saying:"This is my go-to midlayer for alpine climbing and shoulder-season hikes. The Lumina 100 is incredibly lightweight, super packable, and still manages to keep me warm when the temps drop. It disappears into my pack when I don't need it and layers clean under a shell when I do."When we need reliable warmth without the bulk, the La Sportiva Lumina 100 Down Jacket comes with us into alpine terrain and high-output days. This is the lightest piece in the Lumina series, designed for next-level layering efficiency where space and weight matter most. Whether it's worn alone on a brisk fall hike or under a shell for cold belays, this jacket keeps us moving confidently. Built with 1000-fill Italian white down and a recycled Pertex(R) Quantum shell, the Lumina 100 offers incredible warmth-to-weight performance and rugged durability. Strategically mapped baffles enhance loft while maintaining compressibility. The elastic inner sleeve panels improve fit and mobility, and the included stow bag makes it easy to pack down to the size of an apple. It's engineered to be forgotten-until we need it most.