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Marmot Phase 20 Degree Sleeping Bag


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Availability: In Stock!

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Availability: In Stock!

Ships Monday.
Item # MAR9A202M
Weighing roughly a pound and a half, the high-performance Marmot Phase 20 Degree down sleeping bag offers the warmth and compressibility for 3-season backpacking.
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Weighing roughly a pound and a half, the high-performance Marmot Phase 20 Degree down sleeping bag offers the warmth and compressibility for 3-season backpacking.

The bag is insulated with certified 850+ fill power goose down. Fill power measures the loft or "fluffiness" of down insulation and Marmot goes to great lengths to guarantee certification with a battery of in-house and external verifications. Renowned for their efficiency in retaining heat and compressible properties, down fibers have an incredibly soft, comfortable feel and, despite advances in synthetic materials, continue to provide the best warmth-to-weight ratio of any insulation available. The one traditional weakness of down insulation is that it loses much of its ability to maintain warmth when it gets wet. Not so on the Phase, which is protected with Marmot’s Down Defender water-repellent treatment that allows the down to say drier 10 times longer than untreated down in damp conditions. It also maintains significantly more loft and dries faster than untreated down. Pertex 10D nylon ripstop shell and lining help to protect the insulation while keeping weight to a minimum.

Curved horizontal baffles keep insulation from migrating, reducing “dead spots” and ensuring that you experience consistent warmth. An anatomical wrap-around footbox provides comfortable space for your feet and focuses additional insulation there as it is a spot that is vulnerable to losing warmth. Other features include a contoured, ergonomic hood, a full-length two-way zipper that offers a venting option, and anti-snag zipper construction.

The Marmot Phase 20 Degree sleeping bag is available in Regular (fits up to 6' 0") and Long (fits up to 6' 6") lengths.

  • Anatomical Wrap-Around Footbox Increases Insulation and Room for Your Feet, More Warmth and Comfort
  • Smooth-Curved Baffles Reduce Down Shifting. Nautilus Multi-Baffle Hood limits heat loss
  • Full Length Locking YKK Two Way Zipper with Anti-Snag Slider reduces fabric snagging
  • Filled and Finished in Rohnert Park, California
  • Certified 850 Fill Power Down with Down Defender to Improve Water-Resistance in Wet Conditions
  • EN Tested
  • Internal Stash Pocket
  • Snagless Insulated Draft Tube



Best Use Backpacking
Insulation Type Down
Item Weight Regular: 1 lb 7.3 oz
Long: 1 lb 11.2 oz
Other Stuff Sack Included
Warranty Limited Lifetime
Packed Size Regular: 7.5" x 16"
Long: 7.5" x 16"
Shell Material Pertex 10D 100% Nylon Ripstop
Liner Material Pertex 10D 100% Nylon Ripstop
Fits to Length Regular: 6' 0"
Long: 6' 6"
Fits to Girth Regular: 60"
Long: 62"
Fill Material 850+ Fill Goose Down
Temperature Rating 20 Degrees F


Real Customer Reviews

Average Rating:
(based on 6 real customer reviews)

6 Items

Nice and light
Reviewed by TJ - June 29, 2018

Likes: Great sleeping bag, packs quite small and is very light.
Sleeps nice and warm.

Dislikes: The zipper is tricky.
It's a tight fit, not very roomy.

It’s not the zipper, exactly...
Reviewed by Jeff - June 28, 2018

Likes: The Phase 20 is about the lightest full mummy bag available for the temperature rating. The temp rating is at least somewhat conservative. I used it at 25f with light socks and no thermal layers and was quite comfy. It also compresses almost bizarrely small. The supplied stuff sack actually easily fits the bag, a StoS pillow, and a puffy jacket. The hood is deep, and fits almost like a cap. I’m 6’0” and the regular is easily long enough.

Dislikes: Other reviews either hate this bag for the zipper or don’t seem to notice it much, as with the OGL review. The issue, which I think would be obvious if I could post a picture, is the design and fit of the bag itself, not the zipper. The fit above the shoulder area tapers abruptly, and the zipper follows this angle. If your fit in the bag creates pressure at this point, the zipper will not want to move through it. If you don’t, it’s no problem at all.
Other than that, the width in the leg area is rather limited, making side sleeping less comfy.

Superior warmth and comfort!
Reviewed by Anthony D. - May 11, 2018

Likes: I've only tested this once, but in pretty miserable conditions. I love the hood, and really love the footbox insulation. If anything ever gets chilly on me, it's the feet. No problem with this, although in all fairness, I used a Thermolite Reactor Extreme Liner as well. The combination was more than adequate in temps below freezing (down to 25). Packs down nicely, I do use a drysack just to be sure I don't wind up with a soaked bag. Stash pocket was handy for a light....

Dislikes: The zipper is a bit finicky, but the description does say it REDUCES snagging, not ELIMINATES it. Take it slow, no worries...

Worth it.
Reviewed by Dylan C. - February 14, 2018

Likes: Overall this is a great bag. The first night I used it, the temp got down to the high 20's. I slept in my base layer and I was warm enough to sleep well. The next day I forgot to put the cap on my water bottle. After hiking a few miles I lost about a 1/4 liter. It soaked through my pack and through the stuff sack my bag was in. The foot box got a little wet but It still performed fine that night. I definitely think the down treatment makes a difference. Oh and it's super light and stuffs down very small.

Dislikes: It does have a delicate feel to it but I expected that. The thing I really don't like is the zipper. It snags very easily. You can't just passively zip the bag up and go. However after getting a feel for it, I have become much better at using the zippers with out snagging. If the zipper worked a little better I would give it 5 stars because everything is what I expected.

Reviewed by Chris T. - February 3, 2018

Likes: i love love this bag! Super warm, feels amazing and very high quality! i compared this to the rei magma 10 and decided to keep this because i liked the hood system better and the footbox is nicely insulated all around.

Dislikes: yea, the zipper snags

Overall very good lightweight bag
Reviewed by Todd K. - March 25, 2017

Likes: Very lightweight and compressible. Good quality and plenty warm. Used in 30 degree temps and was warm.

Dislikes: Zipper snags sometimes.

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