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Sierra Designs Synthesis 50 degree sleeping bag, yellow and black with white, laying flat fully zipped

Ultralight features. Ultralight price tag.

Built with synthetic insulation and lightweight material typically reserved for a higher price point, the Synthesis packs light but hits heavy with its feature set. A dual zipper system makes getting in and out a breeze and gives you room to move about, while the self sealing foot vent lets you vent heat with ease.

This product is excluded from online promotions.

Key Features

  • Synthetic insulation provides lofty warmth, even when wet
  • Dual zipper system for ease of use
  • Patented self-sealing foot vents for fast and easy ventilation
  • Draft dodger collar helps prevent drafts
  • 20D nylon fabric for lightweight versatility


  • Insulation: Synthetic
  • Shell Fabric: 20d Nylon ripstop
  • Liner Fabric: 20d Nylon Taffeta

Tech Specs


  • EN Limit Temp Rating: 41F / 5C
  • EN Comfort Temp Rating: 49F / 9C
  • Fill Weight: 11oz / 311g
  • Minimum Weight: 1lb 6oz / 626g
  • Fits Up To: 6' 0" / 183 cm
  • Length: 76in / 193 cm
  • Shoulder Circumference: 62" / 152 cm
  • Hip Circumference: 56" / 142 cm
  • Footbox Circumference: 40" / 102 cm
  • Mesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cm
  • Stuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm


  • EN Limit Temp Rating: 41F / 5C
  • EN Comfort Temp Rating: 49F / 9C
  • Fill Weight: 11.9oz / 337g
  • Minimum Weight: 1lbs 8oz / 680g
  • Fits Up To: 6' 6" / 198 cm
  • Length: 82in / 208 cm
  • Shoulder Circumference: 64" / 163 cm
  • Hip Circumference: 58" / 147 cm
  • Footbox Circumference: 42" / 107 cm
  • Mesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cm
  • Stuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm
New Badge: Yes
Gender: Unisex
Insulation: Synthetic
Temperature Rating: 50 Degree
    • Sierra Designs - Synthesis 20/35/50 Synthetic Bag

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    Synthesis 50 Degree

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