The Arc'teryx Atom Men's Vest: the lightweight breathable core protection you need for active pursuits in cold weather. The champion layer under a shell or when you need extra to keep your core comfortable. This has a trimmer pattern cut to stay close to the body through the chest, waist, and hip creating a slim silhouette under a shell. Side stretch panels provide the necessary ease for a full range of movement. A vest to fit comfortably over first layers and tees, and without bulk under both light and winter weight shells. Coreloft™ Compact insulation is designed to take packing, and compacting and bounce back, retains warmth even if it gets wet, and breathes and dries quickly to maintain the optimal climate around your core. A vest that packs into its own pocket for transport and fits into a corner of your pack, it’s warming layer when you take a break.. or the weather takes a turn. With a durable Tyono™ 20 shell to resist wind and light weather this is a vest for active days in winter and sudden surprises in summer.