NEMO Sonic 0 Sleeping Bag

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Stay cozy on frozen mountain bivouacs in the 800-fill-power down comfort of the NEMO Sonic 0 sleeping bag. Adjustable Thermo Gills™ regulate temperature without letting cold drafts in.

  • Features

    • Overstuffed with hydrophobic, PFC-free down; Responsible Down Standard (RDS) certification ensures humane treatment and traceability throughout the supply chain
    • Waterproof/breathable Toester™ footbox is shaped for foot comfort; it has a layer of synthetic insulation to help eliminate cold spots
    • 20-denier ripstop nylon shell fabric and 30-denier nylon taffeta lining feature durable water repellent (DWR) treatments to shrug off moisture
    • Redesigned draft collar and draft tubes provide a secure barrier against cold air; offset zipper creates a thermally efficient seal
    • Contoured hood with drawstring cord maximizes thermal efficiency
    • Stretch construction at the knees allows side sleeping
    • Updated profile holds warmth closer to your body


    Many sleeping bags are rated for temperature by an independent testing protocol. REI and the broader industry now use the International Organization for Standardization (ISO) 23537 protocol, which improves on the older European Norm (EN) 13537 standard; you may still see older items in our assortment that were only EN tested. With either protocol, each bag gets a Comfort (or T-Comfort) rating and Lower Limit (or T-Limit) rating. 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. Ratings are based on a person wearing one long underwear layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38. Many brands use the Comfort rating for women's bags and the Lower Limit rating for men's and unisex bags. Everyone's body and sleep comfort differ, and conditions of use (posture, clothing, sleeping pad R-value, wind, humidity, etc.) affect total insulation, so EN and ISO ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth.
    View all NEMO Men's Sleeping Bags
  • Technical Specs

    Best Use


    Tested Lower Limit

    -1 degrees (F) - EN

    Tested Comfort

    14 degrees (F) - EN

    Temperature Rating (F)

    0 degrees (F)

    Temperature Rating (C)

    -18 degrees (C)


    20-denier ripstop nylon

    Zipper Location


    Insulation Type


    Water-Resistant Down



    800-fill-power hydrophobic down


    30-denier nylon taffeta

    Sleeping Bag Shape


    Stuff Sack Volume

    13 liters




    Down certified to the Responsible Down Standard (RDS)

  • Reviews
    53 reviews with an average rating of 4.2 out of 5 stars

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