Therm-a-Rest Questar 0 Sleeping Bag

$409.95to $469.95
Color: Balsam
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Packed with features needed for cold-weather camping, the Therm-a-Rest Questar 0 sleeping bag offers supreme comfort and versatility on the chilliest of nights.

  • Features

    • 650-fill-power Nikwax Hydrophobic Down™ absorbs 90% less water and dries 3 times faster without using dangerous PFCs
    • With additional room for multiple sleeping positions (W.A.R.M. Fit), means this bag allows for various natural sleep positions while maintaining thermal efficiency
    • SynergyLink™ Connectors let you integrate the bag with a pad (not included) for optimal efficiency and comfort; removable for versatility
    • Zoned down insulation maximizes warmth and saves weight by intentionally placing fill where you need it most
    • Responsible Down Standard certification ensures the down does not come from animals that have been subject to any unnecessary harm, such as force-feeding or live-plucking
    • Shell fabric has a durable water repellent (DWR) to help moisture bead up on the surface
    • Box-baffled construction uses mesh walls to maximize loft and minimize cold spots
    • Toe-asis™ ergonomic toe box rapidly warms cold feet in a pocket of warm down
    • Draft collar, full-length zipper draft tube and cinchable hood help trap heat inside
    • Snag-free zipper; external zip pocket
    • Quilt and blanket loops let you customize your sleep system by layering quilts or tech blankets (not included) for increased warmth
    • Compression sack and storage sack included


    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 Therm-a-Rest Backpacking Sleeping Bags
  • Technical Specs

    Best Use


    Tested Lower Limit

    0 degrees (F) - EN

    Tested Comfort

    14 degrees (F) - EN

    Temperature Rating (F)

    0 degrees (F)

    Temperature Rating (C)

    -18 degrees (C)


    Small: 2 lbs. 9 oz.

    Regular: 2 lbs. 11 oz.

    Long: 3 lbs. 1 oz.


    20-denier ripstop polyester

    Zipper Location


    Insulation Type


    Water-Resistant Down



    650-fill-power Nikwax Hydrophobic Down

    Fill Weight

    Small: 1 lb. 10 oz.

    Regular: 1 lb. 13 oz.

    Long: 2 lbs.


    20-denier polyester taffeta

    Sleeping Bag Shape


    Fits Up To (in.)

    Small: 66 inches

    Regular: 72 inches

    Long: 78 inches

    Shoulder Girth (in.)

    Small: 58 inches

    Regular: 63 inches

    Long: 66 inches

    Hip Girth (in.)

    Small: 58 inches

    Regular: 61 inches

    Long: 64 inches

    Stuff Sack Size

    10 x 8 inches

    Compressed Volume

    6.9 liters




    Down certified to the Responsible Down Standard (RDS)

  • Reviews
    23 reviews with an average rating of 4.0 out of 5 stars

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