$399.00 to $419.00
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Keeping you warm when it's cold outside and cool when the weather warms, the Sea to Summit Ascent AcII sleeping bag does it all with high-quality down insulation and a 3-zipper system for ventilation.

  • Features

    • Ultra-Dry 750+Loft 90% Down Cluster premium duck down is certified to the Responsible Down Standard (RDS)
    • Free-flow zipper system features a full-length YKK® #5 main side zipper, half-length opposite side zipper and a foot zipper to provide ventilation
    • Vertical baffles over the chest prevent down from shifting when you roll over in your sleep
    • Shaped hood, oversize draft collar and zipper draft tube keep the cold out and the warmth in
    • Internal pocket for your phone or other small valuables
    • Form a snug double sleeping bag by zipping to any Altitude Journey or Venture sleeping bag (not included)


    Many sleeping bags are rated for temperature by an independent testing protocol. With both European Norm (EN) 13537 and International Organization for Standardization (ISO) 23537 testing, each bag gets a Comfort (or T-Comfort) rating and Lower Limit (or T-Limit) rating. The Comfort/T-Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit/T-Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Ratings are based on a person wearing one long underwear layer and a hat, sleeping on a single 1 in. thick insulating pad. Many brands use the Comfort rating for women's bags and the Lower rating for men's and unisex bags. Everyone's body and sleep comfort differ, so EN and ISO ratings are simply a guideline to help you compare products.
    View all Sea to Summit Men's Sleeping Bags
  • Technical Specs

    Best Use


    Tested Lower Limit

    15 degrees (F) - EN

    Tested Comfort

    27 degrees (F) - EN

    Temperature Rating (F)

    15 degrees (F)

    Temperature Rating (C)

    -10 degrees (C)


    Long: 2 lbs. 10 oz.

    Regular: 2 lbs. 7 oz.


    20-denier ripstop nylon

    Zipper Location


    Insulation Type


    Water-Resistant Down



    750-fill-power duck down

    Fill Weight

    Long: 1 lb. 5.7 oz.

    Regular: 1 lb. 3.4 oz.


    20-denier ripstop nylon

    Sleeping Bag Shape


    Fits Up To (in.)

    Long: 78 inches

    Regular: 72 inches

    Shoulder Girth (in.)

    Long: 65 inches

    Regular: 61 inches

    Hip Girth (in.)

    Long: 61 inches

    Regular: 57 inches

    Stuff Sack Size


    Stuff Sack Volume

    Long: 14 liters

    Regular: 10 liters

    Compressed Volume

    Long: 7.8 liters

    Regular: 6.2 liters




    Down certified to the Responsible Down Standard (RDS)

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