The UltraTek 470 Long down sleeping bag is the optimum choice for taking on harsh alpine environments. Lightweight and durable, it features a mummy shape design to minimise bulk and reduce air pockets, and RDS 750 fill power down insulation that ensures comfortable warmth down to -9°C. The down itself is treated with DownTek™ to shield it from moisture and prevent clumping, allowing it to insulate even when ice or snow is present. The bag construction is also engineered for superior thermal efficiency, with trapezoidal baffling, a cantered foot box and a 3D hood design with face baffle. The Pertex® fabric shell is both wind resistant and water resistant, and is also treated with a Durable Water Repellent (DWR) finish. For additional comfort, the hood and neck baffle can be tightened to help trap warm air inside. A compression sack and storage sack are both included for storage and travel.