What Our Gearhead(R) Experts Are Saying:"This is my go-to insulation piece when I want max warmth without bulk. The Lumina 100 is insanely light and packs down to the size of an apple. I've tossed it in my ski touring kit, bikepacking bag, and everyday commute pack-it goes everywhere."Whether we're heading deep into the backcountry or just need dependable warmth on chilly transitions, the Lumina 100 Down Jacket is built for maximum insulation with minimum weight. Designed by La Sportiva and packed with premium 1000-fill Italian white down, this ultralight layer punches far above its weight for warmth-to-weight ratio and compressibility. Strategically baffled to maximize loft and thermal efficiency, the Lumina 100 features a tailored fit with internal elastic cuffs for a seal that moves with us. The Pertex(R) Quantum shell is featherlight but durable, making this a layer we can depend on when every ounce counts. Best of all, it stuffs down into its own sack-smaller than an apple-so it's never left behind.