Sea to Summit Flame 15 Review

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 was too warm some evenings.

Credit: 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 bags we tested.

Credit: 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 warm sleeping pad and tent.

Credit: 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 the Nemo Aya. Both products are focused on weight savings.

Credit: 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.

Credit: 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 shell materials are lightweight and translucent so you can see the down through it.

Credit: Ian McEleney

The Sea to Summit Flame is a lightweight choice for long backpacking trips.

Credit: 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.

Credit: Ian McEleney