Useful as a fall belay jacket on its own, or as insulation under a ski jacket, the ultra-lightweight Filament cuts the chill in cool weather, and holds in the heat as a mid-layer in truly nasty conditions.. . Outdoor Research 800-fill down insulation has an incredible warmth-to-weight ratio. Super-packable, DWR-treated 10D Pertex Quantum fabric sheds moisture. Stretch binding at cuffs. Drawcord hem. Full center-front zipper. Two zippered hand pockets. Imported.