Therm-a-Rest · Sleeping Gear
Therm-a-Rest Space Cowboy 45F/7C Sleeping Bag
$146.79
$269.93Save $123.15 (46%)
at REI
Price Historylast 6 months
Low $146.79 · High $148.14. Hover the line to see each change.
Is this a good deal?
- The current price has held for 168 days.
- Across the 16 Sleeping Gear deals we’re tracking right now, the median discount is 35% — this deal’s 46% off is well above that mark.
Based on prices we’ve recorded from REI since April 2026, refreshed several times daily.
About this product
The Therm-a-Rest Space Cowboy 45F/7C is a mummy-shaped synthetic sleeping bag built for backpacking and warm-season camping. Its proprietary eraLoft polyester hollow fiber insulation traps air efficiently to deliver solid warmth without excess weight, and it retains loft even when damp, drying out quickly after exposure to morning moisture. ISO-tested to a comfort rating of 52 degrees F and a lower limit of 45 degrees F (7 degrees C), the bag suits three-season use for a single sleeper. The shell and liner are both GRS-certified 100% recycled nylon ripstop, with a durable water repellent finish on the shell. Heat-mapped zoned insulation concentrates fill where the body needs it most, contributing to a packed weight of just 780 grams (under 2 lbs) and a compressed volume of 8.24 liters. A left-side anti-snag YKK zipper eases entry and exit, while removable SynergyLink Connectors secure the bag to a sleeping pad up to 3 inches thick. A combo stuff and storage sack is included, with a stuff sack size of 8 by 21 inches.
- Category
- Sleeping Gear
- Brand
- Therm-a-Rest
- Material
- eraLoft polyester hollow fiber, 100% recycled nylon ripstop, 100% recycled nylon ripstop with durable water repellent (DWR)
- Color
- CELESTIAL
- Size
- 8 x 21 inches
- Fill
- eraLoft polyester hollow fiber
- Long
- 58 inches
- Shell
- 100% recycled nylon ripstop with durable water repellent (DWR)
- Small
- 56 inches
- Gender
- Unisex
- Lining
- 100% recycled nylon ripstop
What people are saying
Reviewers consistently praise the Space Cowboy 45 for its impressive lightweight and packability, with multiple sources noting it is among the lightest synthetic bags in its class. Its water-resistant synthetic fill earns strong marks, staying dry and warm through morning dew and rainy conditions. The pad-attachment straps and zoned insulation design are appreciated as thoughtful features. The most common criticism is that the temperature rating is misleading: most reviewers find the bag comfortable only down to around 50-52 degrees F, not the advertised 45, and recommend it strictly for warm summer use. Some users also note the foot box could be roomier and the zipper can be finicky.
Specifications
- Warmth
- 3/5
- Breathability
- 2/5
- Packed weight
- 907 g
- Temperature rating
- 7°C
- Sleeping capacity
- 1
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