How to Choose Sleeping Bags for Backpacking
Sea to Summit Ascent AcII 15F Down Sleeping Bag - Long
$324.73Compared to $469.00*Save 30%
Be prepared for unpredictable conditions in the backcountry with the Sea to Summit Ascent AcII 15F | -10C long down sleeping bag—thanks to its high fill power, low weight and heat-retaining design.
Key Details
Fill
750+ fill-power duck down
Weight
2 lbs. 10.2 oz.
Compressed Volume
7.8 liters
Temperature Rating (F)
15 degrees (F)
- Tapered rectangular shape for perfect balance of space and adaptable warmth
- Superlight 20-denier nylon shell and lining fabrics for minimal packed size and maximum breathability
- 750+ fill-power Loft ULTRA-DRY Down for superior insulating power
- Down is certified to the Responsible Down Standard (RDS)
- Generously sized hood and dual cord adjustment for maximum warmth retention
- Vertical chest baffles prevent down migration and cold spots
- Free-Flow half-length zipper on right side; full-length 2-way #5 YKK zipper on left side
- Oversized draft tube with antisnag materials prevents heat loss through the zipper
- Large internal security pocket with flat zipper
- Separate foot zippers for freedom of movement, increased ventilation and dual-use as a quilt
- Anatomic footbox allows maximum down lofting while minimizing heat loss from your feet
- Includes Ultra-Sil™ compression bag for compact storage
- Zip Coupling: This bag is designed to pair with another
- All fabrics and treatments are PFC-free
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 Sea to Summit 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 | 15 degrees (F) - ISO |
| Tested Comfort | 26 degrees (F) - ISO |
| Temperature Rating (F) | 15 degrees (F) |
| Temperature Rating (C) | -10 degrees (C) |
| Weight | 2 lbs. 10.2 oz. |
| Shell | Nylon |
| Zipper Location | Left/Right |
| Insulation Type | Down |
| Water-Resistant Down | Yes |
| Fill | 750+ fill-power duck down |
| Fill Weight | 1 lb. 5.7 oz. |
| Sleeping Capacity | 1-person |
| Lining | Nylon |
| Sleeping Bag Shape | Mummy |
| Fits Up To (in.) | 77 inches |
| Shoulder Girth (in.) | 64 inches |
| Hip Girth (in.) | 64 inches |
| Stuff Sack Volume | 14 liters |
| Compressed Volume | 7.8 liters |
| Gender | Unisex |
| Sustainability | Down certified to the Responsible Down Standard (RDS) |
