Western Mountaineering Bison Gore Windstopper -40C Winter Down Sleeping Bag - Unisex 5002-383

Western Mountaineering Bison Gore Windstopper -40C Winter Down Sleeping Bag - Unisex


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Show Description

Named for a beast that survived ice ages, the bison is crammed with almost a kilo of heat-trapping down. Designed for Denali, Aconcagua, the Himalaya, or anywhere that mistakes could be really quite dire. Huge V-block side baffles and horizontal baffles across your chest hold the down in place. Double interlocking draft tubes and a filled collar seal in heat and security while frigid winds snuffle around the tent.

  • Shell, collar, and draft tube are GORE™ WINDSTOPPER® fabric, which is light, compressible, and impervious to the elements.
  • Deep hood is well filled, and has a large integral hood ruff to seal your face from the elements.
  • Offset, insulated double draft tubes ensure the down doesn't migrate and create cold spots.
  • #5 YKK locking zipper.

Tech specs

Show Tech specs
Ideal for Winter and expedition camping
  • Regular fits to 6' 0" (183 cm)
  • Long fits to 6' 6" (198 cm)

The number of average sized people that the product can comfortably sleep.

Seasons Winter (-15°C to -40°C)
Temperature -40°C
Shape Mummy
Insulation 850+ fill-power goose down
Down weight

The amount of down used to fill the product (measured in grams and given for size medium bags).

Technology GORE-TEX Windstopper
Construction Baffle
Face fabric 30-denier nylon
Lining/backer 20-denier nylon
Packed size 28 x 55cm

The thickness or puffiness of a bag – a key factor in determing a bag's warmth.

Shoulder girth 163cm
Hip girth 140cm
Foot girth 99cm

An insulated collar that covers yours neck and shoulders to reduce heat loss.

Additional feature(s)
  • Draft tube behind zipper
  • Stuff sack included
  • DWR-treated shell fabric
Made in USA