Cosmic 20 Sleeping Bag
Best versatile down bag for budget conscious backpackers.
This sleeping bag is designed for shoulder-season adventures, offering a balance of warmth and packability. It features high-quality down insulation that retains heat effectively while remaining lightweight for backpacking. The mummy shape maximizes thermal efficiency, while the water-resistant finish protects against light moisture. A spacious foot box ensures comfort, and the full-length zipper includes a draft tube to prevent cold air from entering. An internal pocket keeps small essentials secure and accessible throughout the night, making it a reliable choice for camping trips from early spring through late autumn.
$118.22
More Cosmic Options
Owner Satisfaction
4.5
/ 5
Category Rank
1010
/ 2020
#1010 in Sleeping Bags
Price vs Category Average
-29%
Below average
Material
2040050300
/ D T nylon shell, D T polyester liner
Who it's for
- Budget-conscious backpackers seeking reliable warmth without a premium price tag
- Campers in damp climates needing protection against morning dew
- Side sleepers and restless campers who value interior wiggle room
Who should skip it
- Ounce-counting thru-hikers prioritizing a minimal and lightweight pack
- Cold sleepers planning trips where temperatures frequently drop below freezing
- Impatience-prone campers who prefer snag-free, heavy-duty zipper tracks
Performance breakdown
Thermal Efficiency
Mummy shape and draft tube effectively trap heat for shoulder-season comfort.
Packability
Down insulation compresses well, though weight is slightly higher than premium alternatives.
Moisture Resistance
Water-resistant finish handles light dew but struggles in sustained, heavy precipitation.
Foot Box Comfort
Spacious design prevents foot cramping, a rare luxury in mummy-style bags.
Build Durability
Robust nylon shell withstands rough campsite use without sacrificing soft interior feel.
Feature Utility
Thoughtful internal pocket placement makes nighttime essentials easy to grab quickly.
Key Specs
Material
20D 400T nylon shell, 50D 300T polyester liner
Insulation
550-fill duck down
Shape
Mummy
Zipper
Full-length
Max User Height
68 inches
Weight
3.94 lbs
Temperature Rating
20 degrees Fahrenheit
Water Resistant
Yes
Know before you buy
As the name suggests, this bag is rated for 20 degrees Fahrenheit. It is designed for shoulder-season camping, meaning it performs best in early spring through late autumn when temperatures hover around or slightly above freezing.
The Cosmic 20 uses a mummy shape, which is designed to be thermally efficient by keeping the insulation close to your body. While it includes a spacious foot box for comfort, those who prefer a lot of room to sprawl might find the tapered mummy cut restrictive.
The bag features a water-resistant finish on the shell to help repel light moisture and condensation. However, it uses 550-fill duck down, which can lose its insulating properties if it gets soaked, so it is best used in dry to moderately damp environments rather than heavy rain.
No, this specific model has a maximum user height of 68 inches, or 5 feet 8 inches. If you are taller than that, you will likely find the bag too short to comfortably accommodate your height.
The bag includes a full-length zipper equipped with a draft tube, which acts as a barrier to prevent cold air from seeping through the zipper teeth. It also features a draft collar to help seal in your body heat around the neck and shoulder area.
At 3.94 lbs, it is a solid choice for entry-level backpacking or shorter trips where pack weight is a consideration. While it is not an ultralight bag, it offers a good balance of warmth and packability for the price.
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$118