Arc'teryx Men's Cerium Sl Vest Arato 7 - 100% nylon Imported Zipper closure Machine Wash CERIUM SL VEST - As light and compressible as functionally possible, the Cerium SL down vest weighs a scant 120g (4.2 oz) but delivers exceptional warmth for its weight. The 850 fill power goose downs warmth to weight ratio is outstanding, and the tear-resistant, wind resistant Arato 7 nylon shell is exceedingly lightweight. It primarily functions as a midlayer, but its efficient warmth and packability makes it an effective standalone for rest breaks, evenings at camp, or emergency bivvies. FEATURES - Redesign includes two zippered hand pockets, an internal security pocket with a stuff sack, and an adjustable hem drawcord to seal out cold. CERIUM - Streamlined, minimalist and lightweight technical down insulation. High warmth to weight ratio. SUPERLIGHT - Superlight materials and design, emphasizing light weight and packability over durablity. DOWN INSULATION - Highly efficient natural insulation that compacts well and offers excellent warmth to weight.