The ATO – ALPINE TERRAIN OPERATIONS™ MID LOFT JACKET is designed to provide warmth and wind protection when static while avoiding overheating during movement. Constructed with a durable wind resistant nylon fabric that is lightweight and packable. The Polartec® Alpha® Direct insulation is a uniquely constructed knit that does not require a lining layer, reducing the overall bulk but maintaining a high Clo value. The insulation is also highly breathable and designed to allow excellent ventilation during high activity in cold temperatures. Designed to fit over the G3/G4 UNIFORM and Aclima® baselayer tops, and under the COMPACT ALPINE OVERWHITES and under any high lofted outer layer. It can be worn as a concealment outer layer in warmer temperatures and an insulation layer in the cold. It has a roll out helmet compatible hood that is stowed in the collar. Made in US from US materials.