Big Agnes Sidewinder SL 20 Sleeping Bag - Women's

Color: Lyons Blue/Teal
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Ergonomically designed for rolling side sleepers, the Big Agnes Sidewinder SL 20 women's sleeping bag keeps you cozy and comfortable through every roll, turn and flop for a more restful night.

  • Features

    • Ergonomically contoured, technical fit patterned to move with you as you roll from one side to the other, while ensuring warmth and comfort as you settle into position
    • 650-fill-power DownTek™ insulation offers lofty warmth throughout with a PFC-free water repellent finish to keep you dry, even if when wet
    • Body-mapped FireLine™ ECO synthetic insulation alleviates pressure points at the hips and feet while retaining optimized warmth
    • Made from post-consumer recycled polyester, FireLine ECO maintains high loft, compressibility and durability with excellent weight-to-warmth ratio
    • Ripstop shell fabric and smooth, polyester taffeta lining are treated with a PFC-free water repellent finish to help keep you dry and warm
    • Jacket-style hood keeps insulation close around you without sacrificing mobility
    • Stretchy mesh Pillow Barn built into the hood keeps your pillow in place; interior access from either side allows for easy adjustments
    • Specially designed footbox mimics the shape and position of your feet while lying on your side for an optimized fit and thermal efficiency
    • Smooth, antisnag locking zipper and zipper garage ensures no drafty cold spots
    • Low-profile cordlock hood and insulated draft tube allow easy one-handed operation to seal out cold drafts
    • Exterior loops allow you to easily hang dry or store bag when not in use
    • Compatible with virtually every type and size of sleeping pad (not included)
    • Includes storage sack and stuff sack for compact packing


    View all Big Agnes Backpacking Sleeping Bags
  • Technical Specs

    Best Use


    Temperature Rating (F)

    20 degrees (F)

    Temperature Rating (C)

    -7 degrees (C)


    Petite: 2 lbs. 7 oz.

    Regular: 2 lbs. 10 oz.




    Ripstop nylon

    Zipper Location


    Insulation Type

    Down / Synthetic Blend

    Water-Resistant Down



    650-fill-power DownTek/FireLine ECO

    Fill Weight

    Petite: 1 lb. 6 oz.

    Regular: 2 lbs. 7 oz.


    Polyester taffeta

    Sleeping Bag Shape


    Fits Up To (in.)

    Petite: 65 inches

    Regular: 70 inches

    Shoulder Girth (in.)

    Petite: 56 inches

    Regular: 58 inches

    Hip Girth (in.)

    Petite: 54 inches

    Regular: 56 inches

    Stuff Sack Size

    8 x 17.5 inches

    Stuff Sack Volume

    14.4 liters

    Compressed Volume

    Petite: 5.05 liters

    Regular: 5.8 liters




    Contains recycled materials

    Down certified to the Responsible Down Standard (RDS)

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

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