Arc'teryx Atom SL Jacket - Men'sArc'teryx's lightest insulated layer brings warmth exactly where you need it. The Atom SL features recycled stretch insulation concentrated on your core, while uninsulated sleeves and breathable side panels keep you mobile during intense activity. Whether you're tackling shoulder season summits or winter trail runs, this jacket adapts to your pace without weighing you down. Trusted by mountaineers, runners, and outdoor professionals who demand