Big Agnes Sidewinder SL 20 Sleeping Bag - Men's

Color: Legion Blue/Tapestry
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If you're a side sleeper who tosses through the night, the men's Big Agnes Sidewinder SL 20 sleeping bag is ergonomically designed to move with you as you roll, keeping you cozy and comfortable.

Location Image of color Legion Blue/TapestryLocation Image of color Legion Blue/Tapestry
Location Image of color Legion Blue/Tapestry


  • 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)


Regular: 2 lbs. 4 oz.

Long: 2 lbs. 8 oz.




Ripstop nylon

Zipper Location


Insulation Type

Down / Synthetic Blend

Water-Resistant Down



650-fill-power DownTek/FireLine ECO

Fill Weight

Regular: 1 lb. 3 oz.

Long: 1 lb. 5 oz.


Polyester taffeta

Sleeping Bag Shape


Fits Up To (in.)

Regular: 72 inches

Long: 78 inches

Shoulder Girth (in.)

Regular: 61 inches

Long: 65 inches

Hip Girth (in.)

Regular: 55 inches

Long: 59 inches

Stuff Sack Size

8 x 17.5 inches

Stuff Sack Volume

14.4 liters

Compressed Volume

Regular: 4.35 liters

Long: 5.8 liters




Contains recycled materials

Down certified to the Responsible Down Standard (RDS)

25 reviews with an average rating of 4.2 out of 5 stars

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