New product

Due to move this product is unavailable until late 2022.

Zipperless bag. Simple, light and no nonsense. 

More details


Add to wishlist

Pay via Credit Card or Paypal Account
Pay via Credit Card or Paypal Account

Due to move this product is unavailable until late 2022.

If you need this you will know.

High quality 900 fill applied in a generous quantity, cord at the top, light fabrics, no inward taper until hips. Pro tip: down can be shuffled from topside to undersize, or vice versa.

Perfect inside a synthetic over-bag for gnar conditions. 

Concerned about getting in and out of a zipperless bag, and hot weather venting? Look elsewhere.

Sastrugi; snow eroded by wind into ridges. A skier's nightmare.


The Perfect Bag - NO DRAFTS! pics of my Sastrugi.

I got a 28F sastrugi w/ overfill and have used it for ~6 nights without baselayers (male sleeper). The highest night was 48F which was almost too hot for this bag, but it worked okay with leaving the top open. You can also just drape the whole bag over you like a blanket or roll it down halfway on warmer nights. Lowest night was 36F which was really cozy.

I was concerned about the entrance/exit with the zipperless design, but it's not really a big deal, and it eliminates the draft, so I'm happy with it!

It would pair nicely with an apex/alpha quilt (or bivy) for a wide range of use.

Also of note - I'm 5'10 170lb male and got the 70"/62"/40" dimensions and it was roomy! Especially in the torso region, you can fit a huge parka in if you want!

Write your review!

Write a review



Due to move this product is unavailable until late 2022.

Zipperless bag. Simple, light and no nonsense. 

Product Options
Temperature Rating
18°F - minus 8°C
28°F - minus 2°C
Inside Length

To determine the correct length please refer to the measurements in the chart.

In betweener? Use this link

Footbox Size Circumference
40" is the male size 10-11 shoe standard. For side sleepers the 40" is good to size 12-13
Shoulder Width
56" inside circumference. Small frames, skinny people
59" inside circumference. Regular
62" inside circumference. Regular Plus
68" inside circumference. Very roomy.
Shell Material

Two options: Ultralight 10d for the lightest, most breathable and best lofting performance. 15d for more durability and tear resistance with only a small weight penalty.

Liner Fabric
10d Black Taffeta - Lightest, most breathable
Down Type

We use 900 fill power goose down, certified responsibly sourced.

Hyper-Dry moisture resistant down will help combat the effects of perspiration, misting tents and damp air. Nunatak products made with Hyper-Dry down will have a slight increase in bulk over those made with untreated down.

Differential Cut
The standard differentially cut design creates a bigger shell compared to the liner. This allows the insulation to achieve full loft and helps eliminate cold spots.
Yes. Please!
Down Overfill
Adding overfill can prolong the life of the down, help maintain loft during moist conditions, boost the temperature rating by a small amount and keep the down volume from shifting. The amount depends on the product, the size and the rating.
No Thanks
Overfill evenly throughout
Stuff Sack
Our stuff sacks are pretty dope, but current weight saving trends in ultralight circles eschews this once crucial item. So, opt out and save $ while also being very current.
No stuff sack
Yes, please include a stuff sack
Your Measurements
Optional: Fill in the blanks to ensure getting the best fit. No changes will be made to your size selections without approval
Shoe Size