Lightest, most packable Atom Hoody for big efforts in cold, wet conditions.Lighter than the original, the Atom SL Hoody is one of the most useful (and packable) pieces you can own. Wear it as a standalone layer when trail runs take you through cold, wet weather or layer it with a waterproof shell when mountain pursuits demand additional warmth and mobility. Breathable and weather-resistant, it has stretch insulation in the body but not the sleeves or hood — maximizing packability while still delivering focused warmth to your core. What's been updated: Updated with recycled Fortius™ Air 20 fabric, recycled stretch synthetic insulation, and FC0 DWR finish for improved mobility and a lower footprint. New Octa® Fleece side panels give enhanced breathability and less micro shedding. The StormHood™ is now lined and no longer stowable. The Bird logo is embroidered for long lasting visual. Need a heavier option? Try the Atom Hoody .