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Sea to Summit Alpine II Ap2 -15°C High Altitude 850 loft Down Sleeping Bag - Long Length

Sea to Summit

Sale price $638.00 Regular price $1,099.00

Filled with the highest quality RDS 850+ Loft Goose ULTRA-DRY Down, protected by 3D NanoShell, the Sea to Summit Alpine sleeping bag is your cocoon in high altitude and arctic conditions. Designed with a contoured mummy fit and anatomical shaped box foot, warmth is trapped close to the body without a claustrophobic feel. With an oversized neck-collar and hood-seal, drafts are kept out, minimizing heat loss around the face. The oversized zipper draft tube is fitted with the lightest and stiffest anti-snag material for smooth operation. A security pocket located inside the bag is easily accessible, ideal for stowing electronics to preserve battery performance in extreme cold. Using a side block baffle construction to maintain a 60/40 fill ratio means that more down is located in the top of the bag for maximum insulation. The soft touch lining fabric is down-proof by construction and highly breathable, offering a comfortable sleep. The Sea to Summit Alpine series are suited well for for Karakoram expeditions, alpine routes in the Andes, Himalayan high altitude climbing and winters in New Zealand.

Contoured Mummy Shape

The Alpine contoured mummy shape is cut with a fitted hood, broad shoulders and large chest, to accommodate layering of clothing in extreme conditions. Generous room around the knees provides comfort when turning in this bag at night. An oversized foot box affords space for a pair of boot liners to be worn.



  • Contoured mummy, 3D NanoShell, differential cut shell with 3D side walls
  • Offset baffles, 60/40 fill ratio, side block baffle
  • Anatomically tapered box foot
  • Zip draft tube with anti-snag
  • Neck draft tube with dual elastic adjustment
  • Cushioned internal hood draw-cord with dual adjustment
  • 2 way YKK #5 side zip
  • Medium sized internal zip pocket
  • Includes lightweight Ultra-Sil compression bag, mesh storage cell and laundry bag.


 Down Type Ultra Dry 850+ Loft 90/10 European Goose Down
Fill Weight Regular: 710g Long: 780 g
Sleeping Bag Weight Regular: 1365 g Long: 1500 g
Fill Ratio: Top/Bottom 60:40
Baffle Design Side block offset baffle
Shell Design Contoured mummy, differential cut shell with 3D side walls
Outer Shell Fabric 20D Nylon, soft touch, ultra breathable high density down proof weave
Length / Zip Options Regular - left hand zip
Zip Draft Tube Yes with anti-snag
Neck Draft Tube Yes with dual-elastic adjustment
Zip YKK #5 reverse zip
Security/Battery Pocket Yes
Recommended height for user Regular - up to 183 cm  Long: 183 to 195 cm
Chest circumference Regular -154cm  Long: 162 cm

Hip circumference

Regular - 130 cm Long: 136cm

Foot circumference

Regular - 103  Long: 106cm
Season Rating Autumn / Winter
EN Temperature Rating Comfort: -9°C Lower Limit: -15°C Extreme: -35°C
Suggested Use Winter trekking, Snow camping, Ski touring, Alpine climbing, Expeditions
Compressed Volume 10 Litres
Compression Bag Large - 20 to 6.5 Litres