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Sea to Summit Ascent AcII Down Sleeping Bag - (15°F) - Long










The Ascent™ down mummy sleeping bag redefines what versatile means in a sleep system. Complex construction and high-quality down keep you warm when it’s cold outside, while the triple-zipper Free-Flow Zip™ system ensures you stay cool and ventilated when the weather warms.
Shaped to allow a natural sleeping position for comfort, the Ascent is light and compact enough to go everywhere your adventures may take you.
Highlights
Best Use
- Backpacking
Performance
- 2.5 Season: 25°F (comfort range 25°F to 70°F)
- 3 Season: 15°F (comfort range 15°F to 65°F)
- Winter: 0°F (comfort range 0°F to 60°F)
Shape
- More room between hips and knees to allow you to sleep in a natural position without compressing the down insulation and creating cold spots. Far more comfortable than narrow mummy bags for most sleepers.
Features :
• ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS)
• Free-flow zipper system: full-length YKK® #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter.
• Vertical baffles over the chest to prevent down shifting as you roll over in your sleep.
• Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in.
• Internal pocket for phone / GPS / valuables.
• Form a snug double sleeping bag by zipping to any Altitude™, Journey™ or Venture™ sleeping bag.
• Includes lightweight Ultra-Sil™ compression bag and storage cell.
• BEST USE: Backpacking
• COMES WITH: Ultra-Sil™ compression bag and storage cell
• INSULATION: Ultra-Dry Down 750+ Loft
• SHAPE: Relaxed Mummy
• SHELL FABRIC: Lightweight 20D Nylon Shell
• ZIP OPTIONS: Free-Flow zipper system
The Ascent™ down mummy sleeping bag redefines what versatile means in a sleep system. Complex construction and high-quality down keep you warm when it’s cold outside, while the triple-zipper Free-Flow Zip™ system ensures you stay cool and ventilated when the weather warms.
Shaped to allow a natural sleeping position for comfort, the Ascent is light and compact enough to go everywhere your adventures may take you.
Highlights
Best Use
- Backpacking
Performance
- 2.5 Season: 25°F (comfort range 25°F to 70°F)
- 3 Season: 15°F (comfort range 15°F to 65°F)
- Winter: 0°F (comfort range 0°F to 60°F)
Shape
- More room between hips and knees to allow you to sleep in a natural position without compressing the down insulation and creating cold spots. Far more comfortable than narrow mummy bags for most sleepers.
Features :
• ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS)
• Free-flow zipper system: full-length YKK® #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter.
• Vertical baffles over the chest to prevent down shifting as you roll over in your sleep.
• Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in.
• Internal pocket for phone / GPS / valuables.
• Form a snug double sleeping bag by zipping to any Altitude™, Journey™ or Venture™ sleeping bag.
• Includes lightweight Ultra-Sil™ compression bag and storage cell.
• BEST USE: Backpacking
• COMES WITH: Ultra-Sil™ compression bag and storage cell
• INSULATION: Ultra-Dry Down 750+ Loft
• SHAPE: Relaxed Mummy
• SHELL FABRIC: Lightweight 20D Nylon Shell
• ZIP OPTIONS: Free-Flow zipper system