How to Choose Sleeping Bags for Backpacking

The REI Co-op Zephyr 25 is our top REI Co-op brand synthetic sleeping bag, ideal for backpacking from spring through fall. A new extended range of sizes delivers your best fit for better sleep.
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Imported.
Best Use | Backpacking |
---|---|
Tested Lower Limit | 17 degrees (F) - ISO |
Tested Comfort | 28 degrees (F) - ISO |
Temperature Rating (F) | 25 degrees (F) |
Temperature Rating (C) | -4 degrees (C) |
Weight | Short Narrow: 2 lbs. 9 oz. Short: 2 lbs. 12 oz. Medium: 3 lbs. Medium Wide: 3 lbs. 3 oz. Long Narrow: 3 lbs. 2 oz. Long: 3 lbs. 4 oz. Long Wide: 3 lbs. 8 oz. |
Shell | 100% recycled ripstop nylon (bluesign approved) |
Zipper Location | Left |
Insulation Type | Synthetic |
Fill | 100% recycled PET polyester |
Fill Weight | Short Narrow: 1 lb. 13.8 oz. Short: 2 lbs. 0.4 oz. Medium: 2 lbs. 3.5 oz. Medium Wide: 2 lbs. 5.4 oz. Long Narrow: 2 lbs. 5.5 oz. Long: 2 lbs. 6.7 oz. Long Wide: 2 lbs. 9.8 oz. |
Sleeping Capacity | 1-person |
Lining | 100% recycled nylon (bluesign approved) |
Sleeping Bag Shape | Mummy |
Fits Up To (in.) | Short Narrow: 65 inches Short: 65 inches Medium: 71 inches Medium Wide: 71 inches Long Narrow: 77 inches Long: 77 inches Long Wide: 77 inches |
Shoulder Girth (in.) | Short Narrow: 58 inches Short: 65.5 inches Medium: 66.5 inches Medium Wide: 74 inches Long Narrow: 60 inches Long: 67.5 inches Long Wide: 75 inches |
Hip Girth (in.) | Short Narrow: 48.5 inches Short: 56 inches Medium: 57 inches Medium Wide: 65.5 inches Long Narrow: 50.5 inches Long: 58 inches Long Wide: 66.5 inches |
Stuff Sack Size | Short Narrow: 7.75 x 12.5 inches Short: 7.75 x 12.5 inches Medium: 7.75 x 12.5 inches Medium Wide: 7.75 x 12.5 inches Long Narrow: 7.75 x 12.5 inches Long: 7.75 x 12.5 inches Long Wide: 8.25 x 14.5 inches |
Stuff Sack Volume | Short Narrow: 10 liters Short: 10 liters Medium: 10 liters Medium Wide: 10 liters Long Narrow: 10 liters Long: 10 liters Long Wide: 12.5 liters |
Compressed Volume | Short Narrow: 6.8 liters Short: 7.3 liters Medium: 8.3 liters Medium Wide: 8.7 liters Long Narrow: 8.8 liters Long: 8.9 liters Long Wide: 10.3 liters |
Gender | Unisex |
Sustainability | Contains materials that meet the bluesign® criteria Contains recycled materials From a Climate Label Certified brand |
Hip Girth The circumference at the widest point of your hips. | |||
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39-45 | 32-39 | 45-52 | |
Height | |||
4'11'-5'5'' | Short | Short Narrow | Short Wide |
5'5''-5'11'' | Medium | Medium Narrow | Medium Wide |
5'11''-6'5'' | Long | Long Narrow | Long Wide |
Measurements are stated in inches unless otherwise indicated. For Hip measurement, measure around your body at the widest point of your hip. If right at the edge of the measurements listed, size up or down based on your upper body size or how you prefer your sleeping bag to fit. A closer fit will provide better insulation, and a looser fit will allow for a bit more room. It’s important to not have too much room for proper insulation.