Sea to Summit
TK II 18° Sleeping Bag
Product Number: 25342
The Sea to Summit TK II 18 degree sleeping bag, the most versatile bag in the Trek Series, is an excellent companion for winter camping or a long night in a cold train station. This down sleeping bag is EN-rated to a lower-limit temperature of 18 degrees F and a comfort temperature of 30 degrees F.
The Trek Series down sleeping bags are designed with a tapered rectangular shape, which is a happy medium between the comfort of a generous cut and the warmth of a closer fit. Sea to Summit uses premium 650 loft down insulation, with a 2D PermaShell™ DWR (Durable Water Repellent) shell fabric to protect that down from moisture. Innovations like the 3D Sidewall and Reverse Differential Cut keep the insulation in place for maximum thermal efficiency. Temperature ratings are the result of honest, third-party EN testing performed on each sleeping bag.
The TK II features a full-length side and foot zip so it can be opened into a full duvet, for use indoors or in warmer weather. Side block baffles maintain a 60:40 fill ratio, with more down atop the bag where you need it most. The soft-touch lining fabric is highly breathable for comfort. A zipper draft tube minimizes heat loss, with anti-snag material to ensure smooth zipper operation. An oversized security pocket inside the bag is easy to access, and ideal for stashing passports and other valuables while traveling.
The Trek series is Sea to Summit's choice for adventure travel and touring, whether you're sleeping in hostels throughout Europe, backpacking in South America or traveling through the Stirling Ranges in Western Australia. These down sleeping bags are so revolutionary we can’t fit all of the information here, so check out this series of articles on our blog!
* This product does not qualify for shipping to all countries.
- Tapered rectangular
- 2D PermaShell™ DWR shell fabric
- Differential cut shell with 3D side walls
- 60/40 fill ratio
- Side block baffle
- Zip draft tube with anti-snag
- Cushioned internal hood drawcord with dual adjustment
- 2 way YKK #5 zips with separate foot zip
- Large sized internal zip pocket
- Includes lightweight Ultra-Sil® compression bag, mesh storage cell and laundry bag
- Down: 650 Loft 85/15 Premium Down
- Fill Weight: Short: 17.64 oz / 500 grams Regular: 17.64 oz / 500 grams Long: 19.40 oz / 550 grams
- Bag Weight: Short: 2.20 pounds / 1000 grams Regular: 2.25 pounds / 1020 grams Long : 2.43 pounds / 1110 grams
- Recommended Max Height: Short:<5' 5" Regular: <6' Long : <6'7"
- Sleeping bag dimensions Internal circumference (Chest, Hip Foot): Short: 59.05", 58.27," 39.37" Regular: 59.84", 59.05", 39.76" Long : 61.42", 59.84", 40.16"
- Temp Rating: Comfort: 30 DegreeF / -1 DegreeC Lower Limit: 18 DegreeF / 8 DegreeC Extreme: -13 DegreeF / -25 DegreeC
- Zipper Option: Short: Right only Regular: Left or Right Long: Left only
- Season Rating: Indoor/Summer/Spring/Autumn
- Suggested Use: Backpacking, travel, hiking, camping
- Compression Bag: Small - 10L to 3.3L
Gender: Unisex
Zipper Type: Left Zip
Season: F13
Vendor ProductId: 042LL
Review ProductId: 25342
Interested in some of the more technical elements included in the Sea to Summit Trek Series of down sleeping bags? Check out our series of blog articles about these sleeping bag features:
3D Sidewall & Reverse Differential Cut
EN temperature ratings
Reviewed by 1 customer
Displaying review 1
Pros
- Good Loft
- Lightweight
- Packs Small
- Roomy
- Warm
Cons
- The foot construction
Best Uses
- 3 Season Camping
Comments about Sea To Summit TK II 18deg Sleeping Bag:
Western Mountaineering Sycamore MF and TK II 18deg Sea To Summit (STS), my choice was narrowed down to these two to for a bag that could be used full 3 Seasons here in Scandinavia (I live in Denmark)The construction somehow seems to be more advanced on the STS, then the on the WM, I was trying them both in a shop to feel them and read a lot of reviews - The STS won for having a complete package, wash, store, and compression bags comes with it -but also the Zippers and the loft in the bag seams to be better. Update: I have now also some real world experience with it. And for 5 nights it have been living up to my exceptions.
- What Is Your Gear Style:
- Minimalist
- Was this a gift?:
- No
Displaying review 1

















































