Alpine III

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

$468.30 – $489.30

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 at which 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. The same bag will also have a Comfort limit, in the realm of 32°F, so a woman would be comfortable down to an air temperature of 32ºF. Men and women should always sleep in a layer of long underwear and use a sleeping mat with an R-Value appropriate for expected ground temperatures – without this, the sleeping bag itself is unlikely to keep the sleeper warm enough.

Here’s a basic categorization of appropriate use, based on rated temperatures:
Summer:   >+35ºF / +3°C
3-Season:   +10 to +35ºF / -15° to 0°C
Winter:   <10ºF / -15°C

A huge variety of factors can impact sleeping bag warmth - the above temperatures are merely guidelines, not guarantees. It’s important to think of a sleeping bag as one element in a sleep system which also includes an appropriately insulating sleeping pad and a liner. For instance - if you plan on sleeping in nighttime air temperatures of 27ºF / -3°C, choose a bag with a gender-appropriate rating of 23°F / -5°C nights, plus a sleeping mat with an R-Value of 2.5 to 3, and consider a Reactor thermal liner. If you have any questions about which temperature sleeping bag / R-Value sleeping mat you should select, or how to improve your warmth in a sleep system, reach out to us via our contact page any time.

$669.00 $468.30

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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