Serious mountain travel requires an insulated piece with exceptional warmth-to-weight value. The Men's Fission SL Jacket is a lightweight, fully waterproof, insulated jacket that is outstanding in cold wet weather. Gore-Tex full storm weather protection is teamed up with Arc'teryx' laminated ThermaTek non-quilted insulation. The result is evenly distributed warmth that can stand up to anything. No cold spots.There are times when you're working hard but you can't or don't want to remove your insulation. Pit zips let you vent heat rapidly, extending usability on cold days. The insulated StormHood takes care of wind and storms with a fully secure, helmet compatible shelter.Arc'teryx have included two zipped hand pockets, two internal mesh dump pockets, water-resistant Vislon centre front zip, and an invaluable hem drawcord that allows you to really bunker down and have what you need at the ready.