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Big Agnes Men's Sidewinder SL 20 Down Sleeping Bag

MSRP: $249.95
Was: $249.95
Now: $174.96
(You save $74.99 )

Side-Sleeping Comfort

When they discovered that 70% of campers sleep on their side at one point during the night, Big Agnes decided it was time to make a change, and the Men's Sidewinder SL 20 Down Sleeping Bag was born. Taking the thermally efficient design of traditional mummy sleeping bags, Big Agnes gave it a twist, literally, letting you sleep comfortably on your side and ensuring that it's easy to roll over to your other side in the middle of the night. Next, they added extra synthetic insulation in the hips and feet, eliminating common pressure points, so you'll stay comfortable no matter how long you stay on a single side. Finally, they threw in an attached Pillow Barn, so you can shift from side to side without ever leaving your pillow behind again. Say goodbye to sleeping like a stiff plank and say hello to the Sidewinder.


  • Lightweight sleeping bag made with side sleepers in mind
  • Specially constructed to accommodate side-sleeping campers
  • 650-fill Downtek™ provides a high warmth-to-weight ratio
  • Body-mapped synthetic insulation provides extra cushion in the hips and feet
  • Integrated Pillow Barn with stretch mesh keeps your pillow in place
  • Jacket-style hood hugs your face without causing unwanted pressure
  • Water-repellent finish on the shell and liner stop moisture from soaking your insulation
  • Storage bag and stuff sack - Included

Construction + Materials

  • Shell: Nylon rip-stop
  • Lining: Polyester taffeta
  • Insulation: Primary: 650-fill water-resistant DownTek™; Body Mapped: Fireline™ Eco Synthetic Insulation


  • Temp Rating: 20° F
  • Shape: Mummy
  • Best Use: Backpacking, Camping
  • Gender: Men's
  • Zipper Side: Center
  • Fits Up To: [Regular] - 6'; [Long] - 6' 6"
  • Bag Weight: [Regular] - 2 lbs 4 oz; [Long] - 2 lbs 8 oz
  • Fill weight: [Regular] - 19 oz; [Long] - 21 oz
  • Compressed Size: [Regular] - 6.5" x 8"; [Long] - 7.5" x 8"
  • Stuff Sack Size: 8" x 17.5"