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.
- Inclusive sizing lets you find your best fit based on body shape and sleeping preferences
- Semifitted mummy shape provides the roomiest fit of our backpacking bags, offering extra room in the knee area to enable a variety of sleeping positions
- Recycled shell and lining fabrics feature a nonfluorinated durable water repellent (DWR) finish to help moisture bead up on the surface
- 100% recycled synthetic polyester insulation is durable and highly compressible; the fill also retains some insulating ability even if it gets damp
- Shingle construction on top provides uniform loft and helps prevent insulation from shifting and creating cold spots
- Offset quilt construction on the bottom optimizes bag/pad system warmth while reducing unnecessary weight and bulk
- Comfortable hood shape works well for all sleep positions and allows for easy integration with a backpacking pillow (not included)
- 2 differentiated drawcords make the hood easy to adjust while you're zipped in the bag
- Insulated muffler and full-length zipper draft tube keep warmth in and cold out
- Zipper path wraps around the front of your chest so you can more easily zip and unzip the bag; zipper cover and internal antisnag strip allow for frustration-free zipping
- Roomy trapezoidal footbox provides space to move your feet while still remaining warm and cozy
- Keep personal items close and easy to access in the interior stash pocket
- Includes a stuff sack for packing and a roomy mesh sack for breathable storage
- Hand-wash or machine wash warm, gentle cycle in front-load washer only; do not bleach; rinse thoroughly; do not wring; air dry or tumble dry low; do not iron or dry clean
- REI is Climate Neutral Certified; as we work to actively reduce our footprint, we measure annual carbon emissions and purchase an equivalent amount of verified carbon credits
- Contains materials that meet the bluesign® criteria
Imported.
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. For REI Co-op brand nongendered sleeping bags, we provide an overall temperature rating that falls between the Comfort and Lower Limit ratings.
| 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 Narrow: 2 lbs. 13 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 | Recycled ripstop nylon (bluesign approved) |
| Zipper Location | Left |
| Insulation Type | Synthetic |
| Fill | Recycled PET polyester |
| Fill Weight | Short Narrow: 1 lb. 13.8 oz. Short: 2 lbs. 0.4 oz. Medium Narrow: 2 lbs. 1.4 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 | 20-denier recycled nylon (bluesign approved) |
| Sleeping Bag Shape | Mummy |
| Fits Up To (in.) | Short Narrow: 65 inches Short: 65 inches Medium Narrow: 71 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 Narrow: 59 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 Narrow: 49.5 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 Narrow: 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 Narrow: 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 Narrow: 7.8 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 Neutral Certified brand |
Hip Girth The circumference at the widest point of your hips. | |||
|---|---|---|---|
| 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 |
Sizing Notes
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.