The Mythic Ultra Jacket packs in the heat without piling on the weight. Rab thoughtfully crafted this ultra-warm down insulator with 900-fill hydrophobic down insulation for unbeatable warmth at a minimal weight. The Pertex Quantum face fabric keeps wind and weather at bay, and its as packable as the down insulation, allowing the jacket to fit neatly into the included stuff sack. New to Rab, and possible most technical of all, is the Thermo Ionic Lining Technology-or TILT-that sits between the down and the body, reflecting heat for maximum thermal efficiency.