Sea to Summit  Trailhead ThII 30 Sleeping Bag

Members, log in and use coupon code ANNIV24 at checkout to save 20% on this item thru 5/27. Exclusions apply.
Color: Midnight Blue
please select a Size
Select size for delivery dates
Shipping restrictions apply.

A feature-packed yet value-oriented synthetic bag for weekend warriors and new campers, the Sea to Summit Trailhead ThII sleeping bag is no slouch when it comes to performance.


  • Tapered rectangular shape offers more space and comfort than a traditional mummy bag
  • Synthetic insulation continues to keep you warm even if it gets damp
  • Wave Loft construction helps retain warmth and loft
  • Full-length #5 YKK® zipper allows bag to fully open and lie flat for use as a quilt
  • Second zipper in footbox area allows ventilation for your feet
  • Oversized, antisnag zipper draft tubes keep out the chill
  • 30-denier nylon shell fabric is treated with a durable water repellent (DWR) finish that sheds moisture and helps block wind
  • Lightweight 20-denier lining fabric is attached to the shell to prevent tangles
  • Comes with a stuff sack
  • NOTE: This bag is not designed to zip together with another bag


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

Item #152689
Best Use


Tested Lower Limit

30 degrees (F) - EN

Tested Comfort

40 degrees (F) - EN

Temperature Rating (F)

30 degrees (F)

Temperature Rating (C)

-1 degrees (C)


Long: 2 lbs. 10 oz.

Long Wide: 3 lbs. 1.4 oz.


30-denier nylon

Zipper Location


Insulation Type



Synthetic fibers


20-denier nylon

Sleeping Bag Shape


Fits Up To (in.)

Long: 76 inches

Long Wide: 76 inches

Shoulder Girth (in.)

Long: 64 inches

Long Wide: 68 inches

Hip Girth (in.)

Long: 62 inches

Long Wide: 63 inches

Stuff Sack Size


Stuff Sack Volume


Compressed Volume




17 reviews with an average rating of 4.1 out of 5 stars

Loading Reviews...

Questions & Answers

Loading Questions...