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Big Agnes Sidewinder SL 20 Sleeping Bag

sku# 188570
Big Agnes - Sidewinder SL 20 Sleeping BagBig Agnes - Sidewinder SL 20 Sleeping BagBig Agnes - Sidewinder SL 20 Sleeping Bag
Model Info


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Product Info

Built for the side sleepers of the backcountry, the Big Agnes Sidewinder SL 20 Sleeping Bag is one of those things that you see and wonder why it hasn't been around forever. This lightweight, highly packable bag uses strategic mapping of down and synthetic insulations to eliminate pressure points and provide versatile warmth for your overnight adventures. It also provides a snug and secure fit that moves with you as you roll from one side to the other.

Product Details


Shell FabricNylon Rip-stop Fabric with a Durable Water Repellent (DWR) Finish

Lining Polyester Taffeta with a Durable Water Repellent (DWR) Finish


650 fill DownTek™ Primary FillWater repellent down that uses a PFC-Free, bluesign™ approved chemistry.

FireLine™ ECO Synthetic Body Mapped Fill100% post-consumer recycled polyester. Features low-denier fibers that are tightly woven and provide high loft, compressibility, high weight-to-warmth ratio and durability.


Bag WeightRegular: 2lb 4oz / 1.02kg | Long: 2lb 8oz / 1.13kg

Fill WeightRegular: 19oz / 538g | Long: 21oz / 604g

Compressed Bag SizeRegular: 6.5" x 8" / 16 x 20cm | Long: 7.5" x 8" / 19 x 20cm

Stuff Sack SizeRegular: 8" x 17.5" / 20 x 45cm | Long: 8" x 17.5" / 20 x 45cm

Shoulder GirthRegular: 61" / 155cm | Long: 65" / 165cm

Hip GirthRegular: 55" / 140cm | Long: 59" / 150cm

Foot GirthRegular: 36" / 91cm | Long: 40" / 102cm


Specifically Designed for People Who Sleep on Their Sides

Patterned to Move with You as You Roll from One Side to the Other

Optimized Fit and Thermally Efficient Footbox Patterned to Mimic the Shape of Your Foot Position While Lying on Your Side

Smooth, Quick Zip with Anti-snag Locking Zipper with No-draft Zipper Garage and Long Ambidextrous Zipper

Easily Adjust Hood without Unzipping Using Low-profile Internal Cordlock Access

Optimized Warmth and Minimized Pressure Points with Body Mapped Insulation

Seal out Drafts by Cinching Insulated Tube along Upper Hood Opening

Jacket-style Hood Opening Contours to the Shape of Your Face

Pillow Barn Keeps Your Pillow Tucked in Tight

Hang Dry or Store Bags with Exterior Loops

Storage Sack & Stuff Sack Included


  • Insulation: Down, Synthetic
  • Temperature Rating: 20
  • Shape: Mummy
  • Stuff Sack Size: 8 x 17.5"
  • Warranty: Limited Lifetime
Size Long Regular
Length Long Regular
Zipper Location Left Side, Right Side Left Side, Right Side
Max User Height 6'6" 6'
Weight (lbs) 2.5 2.25
Weight (g) 1.13 1.02

Other Notes

Big Agnes products can only be shipped within the United States



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