Sea to Summit Traverse TvIII 15 Sleeping Bag

Color: Forest/Pine
Size: Regular
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The warm and comfortable Sea to Summit Traverse TvIII 15 sleeping bag won't let you down, whether you're hiking through snow to sleep in an alpine hut or camping out after a summer storm.


  • Tapered rectangular shape offers more space and comfort than a traditional mummy bag
  • Proprietary blend of THERMOLITE® insulation uses soft microfibers and fine-denier, hollow-core fibers for lightweight warmth, softness, with high loft and compressibility
  • Anatomically shaped footbox offers extra space
  • Oversize antisnag zip draft tubes and neck draft tube
  • Free-Flow half-zip right side, full-length zip left side and separate foot zips offer freedom of movement and increased ventilation
  • 30-denier nylon shell treated with durable water repellent (DWR) and 20-denier nylon lining are lightweight and compressible fabrics
  • Lining fabrics attached to shell prevents tangles
  • Includes strong 70-denier compression sack
  • This bag is designed to zip with another (second sleeping bag sold separately)


Temperature ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth, since many different factors contribute to your comfort while you sleep. Backpacking bags are typically rated for temperature according to an independent testing protocol—currently International Organization for Standardization (ISO) 23537, though some older items followed European Norm (EN) 13537. Testing is based on a person wearing one base layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38.

Each bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
View all Sea to Summit Backpacking Sleeping Bags

Technical Specs

Best Use


Tested Lower Limit

15 degrees (F) - EN

Tested Comfort

27 degrees (F) - EN

Temperature Rating (F)

15 degrees (F)

Temperature Rating (C)

-10 degrees (C)


Regular: 3 lbs. 2.5 oz.


30-denier nylon

Zipper Location


Insulation Type



Thermolite synthetic insulation


20-denier nylon

Sleeping Bag Shape


Fits Up To (in.)

Regular: 72 inches

Shoulder Girth (in.)

Regular: 61 inches

Hip Girth (in.)

Regular: 57 inches

Stuff Sack Size


Stuff Sack Volume


Compressed Volume




7 reviews with an average rating of 4.6 out of 5 stars

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