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  • Ripstop polyester creates a smooth yet durable shell; polyester taffeta lining breathes for comfort and feels great against skin
  • 600-fill-power DriDown has a water-resistant finish that allows down insulation to resist moisture, dry fast and maintain loft
  • 60 in. dual-slider locking zipper with antisnag design and draft tube to hold in warmth
  • Thermal comfort hood has drawcords of differing widths at head and neck for easy identification and adjustment in the dark
  • Quilt-through construction provides maximum warmth without cold spots
  • Full draft collar drapes comfortably over neck and shoulders, sealing out drafts
  • Natural-fit footbox provides plenty of room so feet don't feel scrunched
  • Stuff sack included


Many sleeping bags are rated for temperature by an independent testing protocol, the European Norm (EN) 13537. Each bag gets two ratings: a Comfort rating and Lower Limit rating. The Comfort rating is the lowest temperature at which the bag will keep the average woman (or "cold sleeper") comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep an average man (or "warm sleeper") comfortable. Everyone's body and sleep comfort is different, so EN Ratings are merely a guideline to help you compare products.

View all Kelty Men's Sleeping Bags

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Best Use Backpacking
EN Lower Limit 40 degrees Fahrenheit
EN Comfort 48 degrees Fahrenheit
Temperature Rating (F) 40 degrees Fahrenheit
Temperature Rating (C) 4 degrees Celsius
Long Right
1 lb. 14 oz.
Regular Right
1 lb. 12 oz.
Shell 50-denier ripstop polyester
Zipper Location Right
Insulation Type Down
Water-Resistant Down Yes
Fill 600-fill DriDown
Fill Weight
Long Right
13 ounces
Regular Right
12 ounces
Lining 50-denier polyester taffeta
Sleeping Bag Shape Mummy
Fits Up To (in.)
Long Right
78 inches
Regular Right
72 inches
Shoulder Girth (in.)
Long Right
64 inches
Regular Right
62 inches
Hip Girth (in.)
Long Right
60 inches
Regular Right
58 inches
Stuff Sack Size 7 x 12 inches
Stuff Sack Volume 7.6 liters
Compressed Volume
Long Right
Unavailable liters
Regular Right
6.3 liters
Gender Unisex
Rated 4 out of 5 by from Weight and size means everything I purchased this bag a month ago and I was not disappointed. I blew the side out of my other sleeping bag washing it, in a pinch I purchased this one as a temporary replacement. I sleep hot so this bag was more than sufficient at 50 degrees outside. I would recommend a silk liner if you expect between 30 and 40 degrees. As for the size I was able to easily put it in the bag pouch at the bottom of my pack. Weight is comparable to my $400.00 20 degree bag which everybody knows weight is everything on a back country hike. All in all for the price, temp rating, and weight this would make an excellent backup bag. If you're just getting into hiking I would really recommend this bag as a primary!
Date published: 2016-08-17
Rated 5 out of 5 by from Fantastic value This is a great bag that lofts well and holds up to its 40f claim. Just a couple items of note. This is a 600 fill bag but the draft guard and the bottom of the foot box are synthetic. The tag claims 75% down minimum to 25% feather but to feel it I'd say it's a little higher, which is a good thing. Wish that the 75% was advertised somewhere prior to purchase, would've liked a higher target. Only questionable thing is tag claims the fill weight is 10.2 ounces but the Kelty website says 12 ounces and REI says 13. Don't think it should be an issue but idk what Kelty is doing there. I also wonder if the 10.2 ounces includes the synthetic fill or is just the down, the bag doesn't specify. Would've liked that almost two-three additional ounces of down. For the price you won't find better for late spring through early fall camping. Don't forget that Kelty also has a pretty broad lifetime warranty.
Date published: 2016-05-30
Rated 5 out of 5 by from Good bag, Great Value Purchased this bag several months ago. Have had it out on the trail a few times now. Performs great. No issues so far. Had it in low 40's high 30's. I slept just fine. I do use a bag liner that adds 5 or 6 degrees to the rating. I'm 6'3" 200lbs. I bought the long and I'm comfortable in it. I sleep pretty hot so this is my go to bag unless temps are going to drop into the 20's Pros: compresses well, light weight, plenty of room, affordable price. Cons: haven't found any at this point. Very happy overall. This bag does what it says it will do.
Date published: 2017-01-27
Rated 4 out of 5 by from Lite & comfortable I used this for out hike on the Chilkoot Trail in Alaska. I stayed comfortable with the temperatures in the lower 40's. Compressed down for easy packing & lite weight.
Date published: 2016-07-26
Rated 4 out of 5 by from Great Buy! Had the opportunity to try these out last week on an overnight in North Jersey. The bag is very light and incredibly easy to pack. Pretty soft and comfortable. Overall very satisfied with the product. Only two minor knocks. One is the zippers could be a little easier to zip. The other is not really a knock, just a warning...the bag is rated at 40 degrees and it works to 40 degrees. I slept in under armor and socks and the outside temp was at 40. Not cold, but not toasty either, so if you're going colder get a liner.
Date published: 2017-04-25
Rated 4 out of 5 by from Unbeatable at the price point Just got back this morning from a beautiful car camp in Prescott National Forest, elevation 6,200 ft. Springtime in Arizona is very diverse and offers amazing outdoor opportunities that can range from 15 degrees to 100. I'm a big guy (6'3 270) and not used to camping, so this was my first sleeping bag purchase. That being said, I was very reluctant to go straight mummy in fear of "sleeping bag claustrophobia." So I found this bag w/a slight relaxed mummy design via great reviews. I went with the 40 b/c I wanted something that could handle the AZ mild cold while also maintaining some degree of use for our warmer climate. I was going for the best all around bag knowing full well that I'll most likely have to have two bags. Re: this review, I've noticed that there don't seem to be too many reviews by us big guys for temp ratings and how they hold up; this one is for the larger folk and "warm sleepers.." The temp was at 40 when I entered the tent (REI Half Dome 2 Plus -- amazing). I had two pair of semi-thick smart wool socks on, a pair of Tru-Spec pants, undershirt/long underwear top/fleece outer, and a standard winter hat (I'm working on the layers, they're expensive). MOST importantly, I was using a Thermarest Basecamp bed roll -- if you're unfamiliar, from what I understand, most bag temp ratings are scaled using a very similar bed roll w/R-Value of 5. It's very important you take note of this b/c it was a lifesaver. Being the novice that I am, I woke up at 2:30am freezing cold b/c I didn't have the bag zipped up fully, haha. So I zipped her up as far as I could and stuffed a sweatshirt in the awesome head pocket that made a perfect pillow. I also pulled my hat down over my face so that virtually no skin was exposed. Let me tell you, if you are worried about the mummy design, don't. I found myself wishing the bag were even tighter, haha. This isn't a knock, however, b/c I truthfully find the dimensions of the bag perfect for me (I bought the "Long" model). Now, maybe others can shed some light on this next point b/c Im not sure it's a legitimate criticism, but I found it annoying trying to fully zip a right-side zipper; I felt like I couldn't get it fully zipped. After these adjustments, though, I fell asleep easily. I still consciously felt cold while I was asleep, but it wasn't b/c of bag failure.. when I woke up at sunrise (6am) it was 28 degrees. I'm guessing that through the night it was reasonable to assume the temps were mid to low 20's. Therefore, I am a fierce advocate the 40 degree rating is solid. Add a bag liner and proper layers, and it's a 30 degree bag for us warm folk. All-in-all, very pleased with this bag at this price point. Kelty really did a great job with the synth/600 down blend. And the icing on the cake: the thing cinches down to a tiny size and weighs incredibly low compared to it's competitors. You can't go wrong with this bag; I would/will buy Kelty again. Hope this helps...
Date published: 2017-03-26
Rated 3 out of 5 by from Does it's job, but just barely I am 6'2" and purchased the long version. It fits me just fine. The only problem I've had is that the way the cowl wraps around my face leaves my mouth and nose in an awkward position. The airflow is a little much. So, it barely passes the 40 degree rating. Also, the bag is extremely thin, so you will need a sleeping pad to go with it.
Date published: 2016-03-10
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Does this have a full-length zipper?

Asked by: athada
The Cosmic Down 40 Sleeping Bag zipper stops 16” from the end of the bag.
Answered by: REIservice
Date published: 2017-05-13
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