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Western Mountaineering - Bison GWS

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Denali, Aconcagua, the Himalaya... mountaineering in the extreme. These are places where the margin for error is zero, and so the Western Mountaineering Bison GWS is most often chosen to serve. A full Gore® Windstopper™ shell makes this bag windproof and virtually waterproof while remaining lightweight and surprisingly compressible. Stuffed with over 40 ounces of 850+ fill down, the Bison GWS has 10 massive inches of heat-trapping loft. Huge V-Block Side Baffles and horizontal baffles across your chest keep the down fill in place, and double Interlocking Draft Tubes and a down-filled Gore® Windstopper™ collar seal in heat while howling winds surround your tent. The huge hood is not only well-filled but is completely made with Gore® Windstopper™ and has a large ruff to seal your face from the elements. The Bison is the crowning glory of Western Mountaineering and demonstrates their commitment to innovation and quality. This life-saving bundle weighs in under 5 lbs and is the warmest bag you'll find anywhere.
Like all of Western Mountaineering's bags, the Bison GWS is made by hand in San Jose, California. Their down is sourced from free-range mother geese who are never live-plucked or force-fed.

International Restrictions Apply

Technical specifications & features

Weight Reg: 4 lbs 10 oz / Long: 4 lbs 13 oz
Gender Men's & Unisex
Color Red
Made in USA
Temp Rating º F -40º F
Temp Rating º C -40° C
Bag Style Mummy
Seasonal Usage Four Season
Insulation 850+ Fill Down
Fill Weight Reg: 42 oz / Long: 45 oz
Bag Shell Material GORE® Windstopper™ 830 Fabric (GWS): windproof, virtually waterproof, and breathable
Bag Length Reg: 6 ft / Long: 6 ft 6 in
Bag Stuff Size 11 x 22 in
Bag Loft 10 inches
Circumference at Chest Reg / Long: 64 in
Circumference at Hips Reg / Long: 55 in
Circumference at Foot Reg / Long: 39 in
Other Features Full GWS down-filled Super Collar completely surrounds your neck for maximum heat retention
Two interlocking GWS oversized down draft tubes mean zero cold spots along the zipper
Footbox made of abrasion-resistant taffeta, a more durable fabric woven with heavier yarns so the inside of your bag is protected when you store gear or boot liners at the foot of your bag
Stiffening tape along zipper to prevent snags
V-Block Side Baffles keep the loft where it belongs
Insulated External Hood Ruff
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