The only jacket that the Mammoth Unbound Park Staff trusts for over 200+ days on snow, the GT Jacket's durability has been upgraded with our exclusive Thermagraph (R) Active lining system to keep you going stronger and longer in any elements. A team favorite, the GT's durable GORE-TEX shell keeps the elements out while the Thermagraph Active (R) lining aids in heat and moisture management as your body heat changes throughout the day. 686 Gore-Tex GT Thermagraph Jacket Mens | Multi Sage | Large | Christy Sports