Big Agnes  Sidewinder SL 20 Sleeping Bag - Women's

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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.

Location Image of color Lyons Blue/TealLocation Image of color Lyons Blue/Teal
Location Image of color Lyons Blue/Teal


  • 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

Item #187789
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)

16 reviews with an average rating of 4.3 out of 5 stars

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