How to Choose Sleeping Bags for Backpacking
Therm-a-Rest Space Cowboy 45F/7C Sleeping Bag
$219.95
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Sleep out under the stars with the worry-free warmth of the Therm-a-Rest Space Cowboy 45°F/7°C sleeping bag. It uses synthetic eraLoft™ insulation to retain warmth even when wet.
Key Details
Fill
eraLoft polyester hollow fiber
Weight
Long: 1 lb. 14 oz.
Compressed Volume
8.2 liters
Temperature Rating (F)
45 degrees (F)
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- Weighing less than 2 lbs. and with a comfort rating of 45°F (7°C), the bag keeps you plenty warm all summer, whether you're road-tripping or heading into the backcountry
- Shell and liner are made of a light and soft, GRS-certified, 100% recycled nylon
- eraLoft insulation is efficient and compressible; the proprietary synthetic insulation uses hollow fibers to trap air and boost warmth without added weight
- Insulation dries fast and retains loft and warmth even when wet
- Heat-mapped zoned insulation delivers an elite warmth-to-weight ratio by allocating insulation to where you need it and reducing it where you don't
- SynergyLink™ Connectors—removable, ultralight straps—create a secure bag-to-sleeping-pad connection that optimizes the comfort and thermal efficiency of your sleep system
- SynergyLink Connectors function best with regular-width sleeping pads (not included) that are 3 in. thick or less when inflated
- Antisnag YKK zipper keeps the bag free of accidental tears and eases entry and exit
- The precision-tuned fit makes sure you have the space you need while eliminating drafts and unnecessary weight
- Combo stuff and storage sack included
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 all Therm-a-Rest Backpacking Sleeping BagsEach 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.
| Best Use | Backpacking |
|---|---|
| Tested Lower Limit | 45 degrees (F) - ISO |
| Tested Comfort | 52 degrees (F) - ISO |
| Temperature Rating (F) | 45 degrees (F) |
| Temperature Rating (C) | 7 degrees (C) |
| Weight | Long: 1 lb. 14 oz. |
| Ultralight | Yes |
| Shell | 100% recycled nylon ripstop with durable water repellent (DWR) |
| Zipper Location | Left |
| Insulation Type | Synthetic |
| Fill | eraLoft polyester hollow fiber |
| Fill Weight | Long: 1 lb. 9 oz. |
| Sleeping Capacity | 1-person |
| Lining | 100% recycled nylon ripstop |
| Sleeping Bag Shape | Mummy |
| Fits Up To (in.) | Long: 78 inches |
| Shoulder Girth (in.) | Long: 65 inches |
| Hip Girth (in.) | Long: 58 inches |
| Stuff Sack Size | 8 x 21 inches |
| Stuff Sack Volume | 17.3 liters |
| Compressed Volume | 8.2 liters |
| Gender | Unisex |
| Sustainability | Contains recycled materials |
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Location:Anacortes, WA
5 months ago
Caution
This product is a good example of ultra lite madness. The literature that comes with it states the comfort temperature is 52 not 45. Didn't notice that until past the return date. Did notice it on a 48 degree morning. Can't be confidently used in Washington State.
3 years ago
the almost perfect sack
I know this doesn't matter at all when it comes to gear but it is nice to such a fun colored bag. I've used it a few times now that I've had it for a month and it is a great bag. The materials are comfortable to sleep in. the length of the bag is great. I am a little bit more broad shouldered then most, and I still fit in the bag well. Only thing in my opinion to make the bag a more versatile bag is if it fully unzipped to use as a blanket on warmer nights. It packs down very nice and is light weight. Would recommend this bag to anyone looking for one.
Review originally posted on a Cascade Designs brand site
1 year ago
I’d make room in my galactic saddlebag for this
Lightweight, comfortable for summer temps, and very compressible for a synthetic bag. I’ve never slept in a mummy style rated for summer temps, but the straps that secure the bag to the ground pad kept the bag in place and I was able to toss and turn (as usual) without any impediment. A wonderful lightweight option for summer trips, and I would bet it would stretch to shoulder season weather with the addition of a quilt or other layered sleep system.
Review originally posted on a Cascade Designs brand site
2 months ago
Love it!!
Yes , I recommend this product
Perfect for me. I’m a side sleeper so there’s only just enough room for my knees when I’m on my side—but just enough is still enough haha. Love the colors, the sleeping pad straps and the two way zipper which allows you vent, or make more room for your knees. Light weight, and easy to pack.This will be a great, most-of-the-year bag in warmer climates. I’m very satisfied. Thanks Thermarest and REI!
3 years ago
Can do it all
Great Bag! Packs up small and is cool enough that I’ll enjoy it in the other 3 seasons but currently using it for winter with the synergy liner and it has been sufficiently warm and light for touring adventures.
Review originally posted on a Cascade Designs brand site
3 weeks ago
So far it’s been the
So far it’s been the perfect bag for van camping! Haven’t taken it backpacking yet, but I’m sure it will be perfect for cool PNW nights.
Review originally posted on a Cascade Designs brand site
3 years ago
Review originally posted on a Cascade Designs brand site