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Kelty Cosmic Down 20 Review

Backpacking Sleeping Bag

Click to enlarge
Best Buy Award
Price:   Varies from $150 - $160 online  —  Compare at 3 sellers
Pros:  Affordable, great value bag
Cons:  550 fill down is heavy and not very compressible, not as warm as other 20 degree bags, roomy cut
Editors' Rating:     
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Manufacturer:   Kelty


The Kelty Cosmic Down is our top choice for budget backpacking and camping. Whether you're new to the outdoors or you want to lighten up your pack, the Cosmic Down 20 is the best way to get started. There are other bags in our current review which are lighter, warmer, and smaller; but the Cosmic Down 20 is affordable and good quality for the price. It is available in other temperature ratings too, just in case 20 degrees doesn't fit your needs. See how well this sleeping bag compares to others in our Backpacking Sleeping Bag Review.

New Version Updates - February 2016
Kelty has confirmed that the Kelty Cosmic Down 20 has been updated. Keep reading to find out more!

RELATED: Our complete review of backpacking sleeping bags

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Analysis and Hands-on Test Findings

Review by:
Mike Phillips
Review Editor

Last Updated:
November 22, 2015

The New Version of the Kelty Cosmic Down 20 vs. The Older Version

Kelty has confirmed that the Cosmic Down 20 has experienced a few new changes in 2016. In addition to upgraded materials and fabrics, the Cosmic Down 20 is now available in new colors and a new style. The fill power has increased from 550 to 600 and the bag still uses hydrophobic DriDown. The list price ranges from $150 to $180 (for the long version).

Check out the side-by-side comparison below, where you'll find the latest version on the left and the older version pictured on the right.
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Hands-On Review

The Kelty Cosmic Down 20 is not a top-of-the-line backpacking sleeping bag. The Cosmic Down is an affordable bag that gets the job done. We're continually impressed with the versatility and quality of this bag at its price point.

Performance Comparison

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The Kelty Cosmic Down 20 (blue) is slightly narrower, but it and the Kelty SB 20 (gray) have similar basic design features including the hood, collar and shape.


The Cosmic Down 20 is not as warm as other down bags in the Backpacking Sleeping Bag Review. This is due to its roomy cut, lower quality 550 fill down, and lower quality fabrics. Without the passive draft collar on this bag we expect that it would be much colder. An adjustable draft collar may be warmer, but may not be as comfortable as the one featured on the Cosmic Down. The bag has a large hood that is not shaped well to the head and shoulders. It did not feel as comfortable and it was colder than a higher loft sleeping bag that has a soft, warm and better shaped hood. The extra down insulation and more articulated draft collar on the The North Face Furnace made it warmer than the Kelty.

Warmer three season bags cost significantly more than the Cosmic Down, so bring extra clothes for cold temps and save some money.


A size long Cosmic Down 20 weighs 43 ounces. This is a similar weight to our Top Pick for synthetic insulation, the Mountain Hardwear HyperLamina Flame. While not lightweight, this is lighter than many bags available for the same price. The Cosmic Down uses 550 fill down, lower quality fabrics, and has a roomy cut. All of these factors contribute to it's heavy weight. Like the lighter weight and slightly higher quality Kelty SB 20 DriDown, the Cosmic Down uses synthetic insulation in the draft tube and collar. We think that by avoiding this synthetic insulation, it could even shave a couple more ounces from this bag. The average weight of the sleeping bags in our review is 37 oz (2.3 lb.), so this bag weighs above that average. Most of those are warmer and pack smaller, but all of them are more expensive.

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800 fill down vs 550 fill. The Kelty SB 20 (top) is a step up in weight savings and packability from the Kelty Cosmic Down (bottom).


The Cosmic Down has a roomy cut which allows you to roll around in your sleep a bit more. That said, testers reported feeling cold in near freezing temperatures, probably due to the dead air space in the bag. We thought that the hood on the Cosmic Down was comfortable in warm conditions when it wasn't on at all, thanks to the roomy collar. When the hood was on, it felt way too big and like it was lacking the softness and loft of a higher quality bag offers to keep your head warm.

Packed Size

The 550 fill down and the lower quality fabrics do not compress as well as higher fill power down and lighter weight fabrics. The other 550 fill bag we tested, The North Face Furnace, was even less compressible than the Cosmic Down. As a down vs. synthetic comparison, the Cosmic Down packs similar in size to the Mountain Hardwear Hyperlamina Flame, a synthetic sleeping bag which won a Top Pick Award. Coincidentally, these two bags weigh the same too.


For an entry level sleeping bag, we were happy to see a down insulation option like the Kelty Cosmic Down 20. Down allows this bag to be lighter, more packable, and more comfortable than some synthetic sleeping bags. It features differential pull cords on the collar that are easy to use. Without the draft collar, we expect that this bag would be much colder. Although we'd prefer to have a full draft collar that cinches close to the neck and shoulders, it is a crucial feature that benefits this bag. Kelty uses synthetic insulation to fill the draft collar and draft tube on the Cosmic Down. We're not convinced that there is any real benefit to this, and if anything we feel that it adds weight and decreases compressibility. The use of water resistant DriDown adds value to this bag.

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The hood on the Cosmic Down is roomy and comfortable. The spacious hood coupled with the passive draft collar may allow some cool night air in if not cinched snugly around your face.


The Cosmic Down will work well as a summer sleeping bag, but it lacks the warmth, weight, and packability for us to consider it a well-rounded 3 season sleeping bag. We haven't tested the Cosmic 0 or the Cosmic 40, but can imagine they would compare in value for their given temperature rating.

Best Application

The Kelty Cosmic Down is best suited for car camping and occasional backpacking. It is a good introductory down sleeping bag for novice or budget backpackers. This bag is warm enough for summer use at low to mid-elevations.


The Kelty Cosmic Down 20 wins our Best Buy Award for its exceptional value. We like the low price, the use of down insulation, and the overall simple design of the bag. At $190 you cannot find another sleeping bag that compares in warmth, weight, and packability.


The Kelty Cosmic Down 20 has been awarded our Best Buy Award again. We feel that it is a good entry level, budget conscious backpacking sleeping bag. It sacrifices weight and packability by using lower quality materials in order to meet its low price-point. This bag is still a good choice for summertime use at low to mid-elevations whether its in your pack or at the campground. Twenty bucks more will get you the comparable North Face Furnace which is warmer than the Cosmic Down but is a big package to carry around on backpacking trip.

Other Versions

Also available from Kelty is the Cosmic Down 0 and the Cosmic Down 40 versions in regular and long sizes. It is also make in a women's specific model. Check out our Women's Sleeping Bag Review to see how the women's specific model compared to other down sleeping bags in that review.

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Cosmic Down 0
  • Weight - 3 lbs 9 oz (1 lb more than the 20)
  • Cost - $290.00 ($100 more than the 20)
  • Shape- Mummy
  • Length- 6ft (long size available- 6' 6")
  • Material- 550-fill hydrophobic DriDown
  • Temperature rating- rated down to zero degrees (20 degrees warmer than the 20)

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Cosmic Down 40
  • Weight - 1 lb 12 oz (13 oz less than the 20)
  • Cost - $140.00 ($50 less than the 20)
  • Shape- Mummy
  • Length- 6ft (long size available- 6' 6")
  • Material- 550-fill hydrophobic DriDown
  • Temperature rating- rated down to 40 degrees (20 degrees cooler than the 20)
  • No top draft collar, like the 20 degree

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Kelty Cosmic Down 20 - Women's
  • Women's version
  • Weight - 2 lb 8 oz (1 oz less than the men's)
  • Cost - $200.00 ($20 more than the men's)
  • Shape- Mummy
  • Length-5ft 8in (4 inches short than the men's)
  • Material- 550-fill hydrophobic DriDown
  • Temperature rating- rated down to 20 degrees
Mike Phillips

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Helpful Buying Tips
How to Choose the Best Backpacking Sleeping Bag - Click for details
 How to Choose the Best Backpacking Sleeping Bag

by Mike Phillips and Max Neale