Alpine III

The perfect sleeping bag for the Queen or King of the alpine start

$669.00 – $699.00

Size Guide

Sleeping Bag Temperature Ratings Explained

The EN Rating scale is a scientific test to determine the warmth of a sleeping bag. Unisex sleeping bags list the Lower Limit which is the lowest temperature rating that an average male sleeper would be comfortable in.  Our women’s sleeping bags list the Comfort Limit, which is the lowest temperature rating an average female sleeper should be comfortable. The comfort and lower limit temperature ratings are listed in the features table on the product page. 

For example, a unisex sleeping bag that shows a lower limit of 23ºF means a man should be comfortable down to air temperatures of 23ºF while a woman would be comfortable down to the air temperature of 30ºF, the comfort limit. Men and women should always sleep in a layer of long underwear and use a sleeping mat.

Here’s a basic categorization of appropriate use, based on temperatures:
Summer:   >+35ºF
3-Season:   +10 to +35ºF
Winter:   <10ºF

There’s a huge variety of factors that can impact sleeping bag warmth, so these ratings are not guarantees. We always recommend choosing a bag that is a few degrees colder than you plan on going out in (choosing a 23ºF bag for 27ºF nights). If you have any questions about which temperature you should select, or how to improve your warmth in a sleep system, reach out to us on our contact page any time.


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The Alpine™ III down sleeping bag is the beefiest sleep refuge within our sleeping bag range and is designed for high altitude expeditions and sub-zero temperatures. It's filled with 850+ loft RDS certified ULTRADRY Down™ and uses 3D NanoShell® for exceptionally effective moisture management. Other well thought out and technically designed features include a side zip draft tube, neck draft tube with dual elastic adjustment to retain warmth, YKK® #5 two-way zipper and a medium sized internal zipped pocket for electronics or essentials. This contoured mummy shaped cocoon is perfect for high altitude base camps, winter backpacking, snow camping, alpine climbing expeditions, and anywhere you need full-scale protection from the cold and a comfortable night on the mountain.


Packed Size Comparison

12.3 L ≈ About the size of a large bear canister


3 lbs 8 oz ≈ Lighter than a standard pillow (does not include the chocolate mint)


Cold Weather! Take this bag out in high alpine conditions in fall, winter, and spring.


Snug, but still plenty of breathing room, tapered foot box wraps feet comfortably for maximum warmth.


  • 3D NanoShell
  • RDS certified ULTRA-DRY Down 850+ Loft 90% Down Cluster Premium Goose Down
  • Season ratings: Fall/Winter
  • Hidden drawcords in a highly-technical hood and draft collar.
  • Side block baffle construction secures down located in a 60/40 top/bottom fill ratio for maximum insulation
  • Differential cut shell (upper), reverse differential cut (lower) allows optimum loft
  • Contoured mummy fit and anatomical shaped foot box
  • 2-way YKK® #5 zipper
  • Includes lightweight Ultra-Sil™ compression bag, combined storage cell and laundry bag