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Sea to Summit Flame 15 Review

A high-tech, high-quality backpacking sleeping bag with more roomy dimensions than most
Sea to Summit Flame 15
Photo: Sea to Summit
Editors' Choice Award
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Price:  $549 List | $379.00 at Amazon
Compare prices at 3 resellers
Pros:  High-quality down, warm and lofty, light, a top tier product
Cons:  Expensive
Manufacturer:   Sea to Summit
By Jessica Haist ⋅ Review Editor  ⋅  May 17, 2019
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89
OVERALL
SCORE


RANKED
#2 of 14
  • Warmth - 25% 9
  • Weight - 25% 9
  • Comfort - 20% 9
  • Packed Size - 15% 9
  • Features - 15% 8

Our Verdict

This year Sea to Summit has launched an impressive line of new sleeping bags, and we were excited to see that they included women's models in their range. The Women's Flame 15 is one of our favorite bags we've ever tested. It has super high-quality materials, an intentional design that keeps its weight down, and it is comfortable to boot. It also packs up tiny, saving precious space in your pack. Can't go wrong here, although its price is certainly a deterrent. The Flame 15 is a great choice for all your long backpacking trips, especially if you'll be high in the mountains and want to stretch your season from early spring to late Fall. This model is a true 3 season bag, even more so when paired with a high R-value sleeping pad.

Compare to Similar Products

 
Awards Editors' Choice Award Editors' Choice Award   Best Buy Award 
Price $379.00 at Amazon
Compare at 3 sellers
$414.00 at Feathered Friends$519.95 at Backcountry
Compare at 2 sellers
$399.95 at Backcountry
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$330 List
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Pros High-quality down, warm and lofty, light, a top tier productHigh-quality down, warm, lightweightLightweight, high-quality materials, comfortableLightweight, compressible, comfortableComfortable, lightweight, excellent materials, not constricting
Cons ExpensiveSizing not for everyone, fabric is a bit noisyExpensive, included compression sack is heavyExpensive, not particularly warmComforter sometimes does not stay tucked in
Bottom Line The premium product comes at a premium price, but is very high performingThe highest three-season performance of any model in our bunchThis bag has high quality materials, is super light, and will fit most womenA great choice for fast and light adventures, the Neutrino is comfortable and compressibleA well-priced, comfortable alternative to a mummy bag that keeps weight low on long backpacking trips
Rating Categories Sea to Summit Flame 15 Egret UL 20 Mountain Hardwear Phantom 15 Rab Neutrino 400 - Women's Cloud 800
Warmth (25%)
9
10
8
7
6
Weight (25%)
9
10
9
10
10
Comfort (20%)
9
8
8
8
8
Packed Size (15%)
9
8
9
9
9
Features (15%)
8
8
8
7
8
Specs Sea to Summit... Egret UL 20 Mountain Hardwear... Rab Neutrino 400 -... Cloud 800
EN Comfort Rating (F) 15 F 20 F (not EN rated) 23 F 21 F 26 F
Fill Type Goose down Goose down Goose down Goose down PFC-Free DriDown
Measured Weight (in lbs) 2.0 lb 1.7 lb 2.0 lb 1.7 lb 1.7 lb
Total Weight (oz) 31.2 oz 27.5 oz 32 oz 27.2 oz 27.4 oz
Fill Power 850+ 950+ 850 800 800
Women specific features Women's specific fit - more insulation in key areas Extra fill in footbox and chest This bag comes in a "Short" length, which is a standard women's size Women's specific fit More insulation per square inch than men's version
Fill Weight (oz) 22.9 oz 17.3 oz (medium) 20 oz 14.1oz 14.8 oz
Material Ultralight 10D Nylon Shell Pertex Endurance UL 10D nylon ripstop Pertex Quantum 15d nylon risptop
Neck Baffle Yes Yes Yes Yes No
Pocket No No No Yes No
Sleeping Pad Sleeve No No No No Yes
Zipper Length 56" 62" 59" 62" N/A
Shoulder Girth 60 in 54 in 58 in 60 in 59 in
Hip Girth 58 in 56 in 52 in 56 in 58 in
Foot Girth 40 in 38 in 44 in 38 in 39 in
Stuff Sack included? Compression stuff sack and storage bag included Stuff sack and storage bag included Compression sack and storage bag included Stuff sack and storage bag included Stuff sack and storage bag included

Our Analysis and Test Results

With 850-fill power goose down and lots of it, the Flame is very warm, light, and lofty. We love this bag and think it's an excellent choice for lightweight backpacking. It's pricey, but it's also widely available and firmly lands in the top echelon of women's backpacking sleeping bags we've ever come across.

Performance Comparison


The S2S Flame 15 is super warm. At low elevation in the summer it...
The S2S Flame 15 is super warm. At low elevation in the summer it was too warm some evenings.
Photo: Jessica Haist

Warmth


This bag is EN-rated to 15 degrees Fahrenheit, and we think that rating is spot-on. The Flame has almost 23 ounces of high quality 850 fill power down that is super lofty and fluffs this bag right up. It is neck and neck with the other top contenders in this review in this rating metric.


The Sea to Summit Flame - Women's is one of the warmest and loftiest...
The Sea to Summit Flame - Women's is one of the warmest and loftiest bags we tested.
Photo: Ian McEleney

The Flame also has huge fluffy neck baffles around the front and back to stop any pesky drafts from coming in down your neck. Sea to Summit claims the Flame has "down chambers filled using body-mapping to maximize warmth for a woman's physiology." We're not sure what this means, but half of its baffles are sewn vertically while the lower ones are horizontal; the jury is out whether this makes a difference in warmth.

You can stretch this warm bag into the winter months paired with a...
You can stretch this warm bag into the winter months paired with a warm sleeping pad and tent.
Photo: Jessica Haist

Weight


Weighing in at 1.95 pounds, this bag is not the most lightweight model we've ever jumped inside, but it's not heavy either. It's just a smidge heavier than the lightest models we tested. However, those bags are not as warm as the Flame, which makes up for the few extra ounces.


The 10D nylon shell material is very light and thin, yet we didn't experience any durability issues during testing. They are translucent—you can see the down feathers and clusters right through the materials.

Two of our lighter additions this round, the Sea to Summit Flame and...
Two of our lighter additions this round, the Sea to Summit Flame and the Nemo Aya. Both products are focused on weight savings.
Photo: Ian McEleney

Comfort


We were pleasantly surprised by how comfortable the Flame is. It is a simple mummy shape that is roomy enough to move around a bit and fit our 5'5 tester very well. It is so light and fluffy; it feels very cozy.


The spacious dimensions, yet high scores in warmth and weight, complete an ideal backcountry trifecta. You might be able to cut a little weight or gain a bit more confined warmth, but overall, this bag nails the combination of these aspects better than nearly any bag out there.

Packed Size


The Flame comes with a great compression sack that will pack this bag down super small. This bag takes a bit more effort to get into its compression sack as the materials seem to have a waterproof coating that takes effort to get the air out of when compressing it down. That said, Sea to Summit's inclusion of a compression sack, as opposed to a simple stuff sack, is a huge bonus for this bag, making stuffing it into the smallest packed spaces easier.


The Flame (left) and the Aya in their included compression sacks.
The Flame (left) and the Aya in their included compression sacks.
Photo: Ian McEleney

Features


This bag has very limited bells and whistles, which we like. The high-quality materials and streamlined design are a simple, weight-saving feature. We do wish it had a small stash pocket for those essentials like a headlamp or earplugs we want during the night. We also noticed that the zipper is not particularly high-quality and prefer ones with anti-snag pulls.


The Flame comes with a strange rectangle-shaped "case" for storage. We do not like it at all. It is difficult to get the bag back in the case, and it leaves the Flame partially compressed during storing, which is less than desirable.

The Sea to Summit Flame has very high quality down fill and it's...
The Sea to Summit Flame has very high quality down fill and it's shell materials are lightweight and translucent so you can see the down through it.
Photo: Ian McEleney

The Sea to Summit Flame is a lightweight choice for long backpacking...
The Sea to Summit Flame is a lightweight choice for long backpacking trips.
Photo: Jessica Haist

Value


Here is this product's one Achilles heel - it's one of the most expensive bags we tested. This aspect is the one reason we would hesitate to buy it.

Conclusion


We love this bag and commend Sea to Summit for putting out such a technical product for women. It is top-notch in nearly every single way. We wish all manufacturers would put this much intention into new products for women. The Flame is light, super warm and lofty, and very comfortable. Now, if we could just work on getting that price tag down a bit…Regardless, this sleeping bag is a fantastic option for anyone going deep into the backcountry.

The women's Flame has a very warm hood and interior draft collar.
The women's Flame has a very warm hood and interior draft collar.
Photo: Ian McEleney

Jessica Haist