With A Minimalist Design Providing Core Warmth For Very Little Weight, The Cerium Lt Vest Performs As A Midlayer Or Standalone In Cool, Dry Conditions. Premium 850 Fill Down Is Resilient And Warm, The Arato™ 10 Shell Provides Lightweight Durability, And Down Composite Mapping™ Strategically Places Coreloft™ Synthetic Insulation In Moisture-prone Areas. The Women’s Specific Trim Fit Layers Easily Under A Shell, And The Sewn-through Construction Further Reduces Weight And Increases Packability.