How to Choose Sleeping Bags for Backpacking
Therm-a-Rest Space Cowboy 45F/7C Sleeping Bag
$139.73 – to $149.73Save up to 31%
Sleep out under the stars with the worry-free warmth of this Therm-a-Rest 45°F sleeping bag. The synthetic eraLoft™ insulation retains warmth even when wet. It shrugs off morning dew and dries fast.
Key Details
Fill
eraLoft polyester hollow fiber
Weight
Small: 1 lb. 10 oz.
Regular: 1 lb. 12 oz.
Long: 1 lb. 14 oz.
Compressed Volume
8.24 liters
Temperature Rating (F)
45 degrees (F)
- 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 light and soft, GRS-certified, 100% recycled nylon; GRS-certified 100% recycled fabrics are eco-friendly while being lightweight, soft and durable
- 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
- Precision-tuned fit makes sure you have the space you need, while eliminating unnecessary drafts and weight
- Antisnag YKK zipper ensures easy entries and exits and prevents accidental tears
- 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
- Includes a combo stuff and storage sack
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 | Small: 1 lb. 10 oz. Regular: 1 lb. 12 oz. Long: 1 lb. 14 oz. |
| Shell | 100% recycled nylon ripstop with durable water repellent (DWR) |
| Zipper Location | Left |
| Insulation Type | Synthetic |
| Fill | eraLoft polyester hollow fiber |
| Fill Weight | Small: 1 lb. 4 oz. Regular: 1 lb. 7 oz. Long: 1 lb. 9 oz. |
| Sleeping Capacity | 1-person |
| Lining | 100% recycled nylon ripstop |
| Sleeping Bag Shape | Mummy |
| Fits Up To (in.) | Small: 66 inches Regular: 72 inches Long: 78 inches |
| Shoulder Girth (in.) | Small: 57 inches Regular: 62 inches Long: 65 inches |
| Hip Girth (in.) | Small: 56 inches Regular: 57 inches Long: 58 inches |
| Stuff Sack Size | 8 x 21 inches |
| Stuff Sack Volume | 17.3 liters |
| Compressed Volume | 8.24 liters |
| Gender | Unisex |
| Sustainability | Contains recycled materials |
Buying Advice
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4 weeks 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!