We designed the warmest jacket in our Atom family with industry engineers, scientists, and hardcore athletes who understand that staying warm is staying safe. Female-specific thermo-mapped insulation (warmer 120gsm in the body, stretchy 60gsm in the pits) strategically traps and dumps heat, so you won't get soggy even when you're working for that summit. A cornerstone of an all-conditions layering system, the Atom SV delivers serious protection on its own, and teams up with a hardshell to keep out any storm. Need a lighter option? Try the Atom Hoody .