Stay warm. Stay focused. The Nuclei SV - our warmest synthetically insulated belay parka - delivers outstanding thermal performance. Varied layers of Coreloft™ insulation are strategically placed to combine maximum warmth with lightweight packability, and the light, tough Arato 15 shell is breathable, windproof, and has a DWR finish to repel light moisture. Three external and two internal pockets keep essentials at hand, and the helmet compatible StormHood™ protects without impeding vision.