Arc'teryx developed the warmest jacket in the Atom series with input from engineers, scientists, and elite athletes who prioritize safe warmth. The female-specific thermo-mapped insulation—featuring 120gsm in the body and stretchier 60gsm in the underarms—effectively retains heat while allowing moisture release, preventing dampness during intense efforts. As a key piece in a versatile layering system, the Atom SV provides substantial standalone warmth and pairs seamlessly with a hardshell to protect against harsh weather. Updated with recycled Coreloft™ insulation and DWR (Durable Water Repellent) free from intentionally added PFAS. Hood design has been updated for better weather protection and easier repairability.