Kelty  Cosmic Down 0 Sleeping Bag

$204.73 – to $219.73Save up to 25%

Remember trapezoids from 10th-grade geometry? This funky shape is ideal for helping sleeping bag baffles retain heat and is just one of the reasons the Kelty Cosmic Down 0 bag is a 3-season superstar.

Color: Fired Brick/Red Ochre
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Features

  • Lightweight and warm 550-fill-power down
  • Innovative trapezoidal baffle construction improves thermal efficiency
  • Buttery-soft and durable 20-denier nylon shell fabric with PFAS-free durable water repellent (DWR)
  • Zippered internal stash pocket for headlamp or cellphone
  • Zipper draft tube with anti-snag zipper design makes it easy to get in and out
  • Dual slider for ventilation with locking zippers
  • Natural-fit spacious footbox offers extra room to wiggle your toes
  • Comes with stuff sack for quick departures

Imported.

Temperature ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth, since many different factors contribute to your comfort while you sleep. Backpacking bags are typically rated for temperature according to an independent testing protocol—currently International Organization for Standardization (ISO) 23537, though some older items followed European Norm (EN) 13537. Testing is based on a person wearing one base layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38.

Each bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
View the Kelty Cosmic Product LineView all Kelty Backpacking Sleeping Bags

Technical Specs

Best Use

Backpacking

Tested Lower Limit

4 degrees (F) - ISO

Tested Comfort

17 degrees (F) - ISO

Temperature Rating (F)

0 degrees (F)

Temperature Rating (C)

-18 degrees (C)

Weight

Regular: 4 lbs. 5 oz.

Long: 4 lbs. 10 oz.

Shell

20-denier nylon taffeta

Zipper Location

Right

Insulation Type

Down

Fill

550-fill-power down

Fill Weight

Regular: 2 lbs. 7.5 oz.

Long: 2 lbs. 9.6 oz.

Sleeping Capacity

1-person

Lining

50-denier polyester taffeta

Sleeping Bag Shape

Mummy

Fits Up To (in.)

Regular: 72 inches

Long: 78 inches

Shoulder Girth (in.)

Regular: 62 inches

Long: 64 inches

Hip Girth (in.)

Regular: 58 inches

Long: 60 inches

Stuff Sack Size

10 x 19 inches

Stuff Sack Volume

Unavailable

Compressed Volume

Unavailable

Gender

Unisex

Buying Advice

A sleeping bag inside a backpacking tent

Reviews
6 reviews with an average rating of 3.8 out of 5 stars

Ratings Snapshot

Product Rating

2 out of 4 (50%) reviewers recommend this product

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Flaca76
Rated 5.0 out of 5 stars

Great on the trails

1 month ago

This sleeping bag is wonderful. I've used it on Mt. Whitney, Mt. Shasta, and Mt. Baldy, and it's perfect for me! I've had it for 3 years.

Age:45–54
Yes , I recommend this product
Helpful?
Greg
California
Rated 5.0 out of 5 stars

Great 0 degree bag at great price

10 months ago

Used this for the first time up at 12k altitude as an upgrade from my Kelty Cosmic 21 bag knowing it was going to be a cold trip. Well with frost on the tent, I was snug and warm inside. The zipper is large and easy to maneuver at night in the dark. The last night of the trip was warmer so opened up from the bottom of the bag for the body to get some cooler air in. Overall, if you're looking for a warm bag at a great price, I highly recommend.

Age:35–44
Yes , I recommend this product
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Padre E
Tucson AZ
Rated 1.0 out of 5 stars

0 degrees C maybe (32 degrees F) but barely that

6 months ago

I’ve had this bag 4 or 5 years. Using it in Arizona mountains in fall and winter, temps around freezing, I get cold in this bag even when inside a tent, wearing layers of Smartwool, fleece, a down puffer jacket, fleece beanie cap, and sleeping on a thick Paco Pad and space blanket tarp. This is nowhere near a 0 degrees Fahrenheit bag. Maybe 40 degrees F.

Age:55–64
No, I do not recommend this product
Helpful?
Eli
Rated 4.0 out of 5 stars

Warm, comfortable, ugly.

6 months ago

Real warm. Not the most handsome design in my opinion. Wife says it’s a bonus though- because no one will want to steal them.

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JTurner07
Virginia
Rated 3.0 out of 5 stars

Good for back sleepers

5 months ago

Nearly impossible to sleep on your stomach if you’re of larger size. Very warm over all though I just can’t sleep on my back. I am 6 feet 3 inches tall 250 pounds for reference

Age:18–24
No, I do not recommend this product
Helpful?
Bill47
Rated 5.0 out of 5 stars

For "Cold sleepers"

5 months ago

Haven't had a chance to try it, but it's gorgeous and feels like it will live up to the temp rating.

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