Performing as midlayer and standalone across a broad range of activities and output levels, the iconic Atom LT is an Arc‘teryx mainstay. Over time, we have refined the design to elevate performance, improve durability and extend its versatility. Its Coreloft Compact insulation retains heat when wet and withstands repeated packing and unpacking. Light, soft and durable, the Tyono 20 face fabric resists wind and weather, and stretch fleece side panels improve ventilation and freedom of movement. Moisture-resistant outer face fabric. Breathable. Insulated. Lightweight. Wind resistant. Performance stretch fleece side panels give ventilation. Trim fit for base layer or light mid-layer use. Internal chest pocket with zip. Two hand pockets with hidden zippers. 100% Nylon .Care Instructions: Machine wash in cold water on a gentle cycle, do not bleach, tumble dry on low heat on a delicate setting, do not iron, do not wring and do not dry clean.