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Sea to Summit Altitude AT I Sleeping Bag Long Women arctic/ocean

ID: 1137284

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Product description

Sea to Summit Altitude AT I Sleeping Bag Long Women arctic/ocean (arctic/ocean)

Engineered for women to provide extra warmth where needed, be prepared for the unpredictable with the adaptable Altitude Series bags.

Offering the perfect backpacking balance of comfort vs weight, the Altitude Series sleeping bags have more space than traditional mummy bags, yet still provide the thermal efficiency you need when exploring above the tree-line.

The Free-Flow triple-zip design ensures your sleeping bag retains maximum warmth and efficiency when needed and multiple ventilation options when it’s not. The half zip on the left side of the bag provides freedom of movement for both arms, additional ventilation and also means the top third of the bag can be folded down as a mini quilt. The full length, two-way right side zip and separate foot zip transforms the bag into a full quilt for when the mercury climbs higher than expected.

If it’s warmth you’re after, close all the zips, pull the cord locks tight to drag everything in, and relax in luxurious comfort. The generous allocation of high quality 750+ Loft down ensures great insulation, while the oversized draft tubes prevents your body heat escaping. The panelled footbox and 3-dimensional hood make sure you’re not compressing the down when you’re trying to stay warm. The Altitude also features extra down overall and Thermolite panels under the foot area, to help keep heels and ankles warmer.

Vertical baffles over the chest section ensure the down insulation cannot migrate or shift to the outside of the bag during sleep, creating cold spots. A side block baffle construction maintains the 60/40 fill ratio, keeping more down on the top of the bag for maximum insulation.

The tapered rectangular design gives you additional wriggle room inside the bag, perfect for a side or restless sleeper and an alternative if you find a traditional mummy shape too constricting. The women’s specific fit is wider at the hip and narrower at the shoulder and comes in two lengths.


  • Women's specific Tapared Rectangular cut for a perfect combination of space and adjustable warmthFor a perfect combination of space and adjustable warmth
  • More down and Thermolite in the foot area for warmth
  • Super light 20D nylon sleeve for minimum packing size and maximum breathability
  • RDS 750+ Loft Ultra-Dry Down for excellent insulation
  • Vertical chambers in the chest area optimise the distribution of down and prevent cold bridges
  • Half-sided free-flow zipper on the right side and a full-sided #5 YKK zipper on the left side
  • Separate zipper on the foot box allows free space, improved ventilation and versatile use
  • large zipper channels with Anti-Snag prevent body heat from escaping
  • Oversized thermal collar with dual adjustment system
  • Anatomically shaped foot box maximises the bulk of the down and reduces heat loss through the feet
  • Zip Coupling: This sleeping bag can be zipped together with other models
  • Outside slot

Special Features

Responsible Down Standard (RDS)

The Responsible Down Standard (RDS) aims to ensure that down and feathers come from animals that have had their nutritional, physical and emotional needs met. This means that force-feeding and live plucking is prohibited, and that the full supply chain is evaluated from the farm to the final product.


Bike Travel, Wild Camping, Campsite Camping, Bikepacking, Trekking
Main Information
Down sleeping bag
Mummy form
Fill Power (cuin):
750 cuin
Down Mix (Down/Feather):
Temperature Range
Comfort Temperature (°C):
Temperature limit:
-12.00 °C
Extreme temperature:
-31.00 °C
Upper Material:
20D Nylon
Cover material detail:
100% nylon
Inner Fabric:
20D Nylon
Lining detail:
100% nylon
Goose down
Special features:
Contains non-textile parts of animal origin
Sleeping bag:
1,170.00 g
580.00 g
Body height (max):
179.00 cm
Sustainability Standard
Sustainability certificates:
Responsible Down Standard (RDS)
Model Year
Article number

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