The popular Atom SL Hoodie jacket is updated with new fabrics and a button to stow the hood when it's not in use. Coreloft 40 insulation is light, breathable, compressible and packable; insulation is strategically placed at the chest and back to keep the jacket light and compressible. Tyono 20 outer material balances airflow with wind resistance and has a durable water repellent (DWR) finish to repel moisture. Stretch fleece side panels allow ventilation. Adjustable, low-profile uninsulated StormHood stows out of the way with a button when you don't need it. Uninsulated, mesh-lined sleeves give light protection and regulate temperature. Articulated elbows and gusseted underarms allow for good mobility and comfort. Full-length zipper with chin guard and windflap. Adjustable hem drawcord; dropped back hem. 2 zippered hand pockets. Trim fit for use as a base layer or light mid layer. Contains materials that meet the bluesign criteria.