Gear Review: Sea to Summit Ember II 30 Down Quilt

Backpacking quilts have gained  in popularity in recent years, largely driven by weight-conscious backpackers looking to trim weight from their sleep system. Properly used, a quilt can keep you just as warm as a mummy bag. By eliminating the zipper and the insulation you would otherwise be crushing with your body, quilts cut weight without sacrificing (too much) warmth. The Sea to Summit Ember II Quilt is a warm-season quilt that is best used fully opened as a blanket, but can be cinched up for greater warmth on chilly nights. 

Sea to Summit Ember II At-a-Glance

Temperature Rating: 30°F
MSRP: $329
Bag Weight: 1 lb 4 oz
Fill Weight: 12 oz
Packed Size: 6 x 7 inches
Materials: 850+ fp Ultra-Dry Down, 10D Nylon Shell, 7D Nylon Liner
Length: Suitable for a person up to 6′

Circumstance of Review

I used this quilt all summer long on a variety of camping and hiking trips. I slept in it in a tent, under a tarp, and cowboy camping. While I usually had pleasant weather, I did get a few cold and damp nights at high altitude, and plenty of windy ones. 

Sea to Summit Ember Features

Snap-on Attachment Straps: The quilt comes with snap-on attachment straps to secure the quilt around your sleeping pad on cold nights. While it is a nice feature and functions well, the snaps come undone fairly easily, which can be an issue for a restless sleeper. 

Drawcords at the Head and Foot: The drawcord at the bottom can be cinched up to make a footbox on cold nights. Similarly, the cord at the head cinches the quilt around your neck. While both features were nice to have on colder nights, the top doesn’t cinch up quite as securely as some other quilts I’ve used, making it a little drafty if I move around a lot. 

Temperature Rating Accuracy

In my personal experience, the temperature ratings of sleeping bags and quilts are never very accurate. Aside from the fact that bags are rated while paired with an insulated pad far thicker than the average backpacker would use, they are also rated for men, who tend to feel warmer than women at the same temperature. I’ve learned that it’s best for me to add about 10 degrees to the bag or quilt rating for a more realistic comfort rating. 

Sea to Summit rates the Ember II at 25-35 degrees. For me, it has proven comfortable according to my usual rule of adding 10 degrees. The quilt is comfortable for me between 35-45 degrees. When it dips below that, I’m buttoned and cinched up with my puffy on to stay comfortable. If it were to actually get down to 25, I’d have a pretty cold night, but I’d survive. I personally wouldn’t take this quilt along if I expected temperatures to dip below freezing with any regularity. 

As a Double Quilt

One feature I was super excited about with the quilt was the ability to snap it together with another one to make a two-person quilt, and my husband and I took two along on a section of the PCT to test this feature out. Unfortunately, in practice it didn’t function well. Like the straps, the snaps came undone far too easily. In addition, there was no baffle or other feature to keep the attachment seam from being extremely drafty. It was warmer and more comfortable for each of us to use our quilts separately. 

Sleep System Details 

In order for a quilt to function effectively, it should be used as part of a system. This system involves an insulated pad, insulation for your head, and layers of clothing. Given the temperature rating of the quilt, it should be paired with a pad with an R-value between 2.0-3.3, which is pretty typical for lightweight backpacking pads. Combining this quilt with my inflatable pad and wool buff, I am comfortable in a wide range of temperatures. On warm nights, I can shed layers and open the quilt like a blanket. When it gets chilly, I cinch up the footbox and put on socks to keep my feet warm. And on cold nights, I secure the quilt around my pad or my body, cinch it around my neck, and add more clothing layers to increase insulation.   

This is a down quilt, and therefore provides an excellent warmth-to-weight ratio. Like most modern quality down bags and quilts, the down is treated to increase its resistance to moisture. However, that doesn’t make down waterproof. If the quilt is damp in the morning, it is important to air it out at some point during the day, or the quilt won’t dry out, and a damp down quilt won’t keep you as warm. 

Ember II Pros

Fully Opening Footbox: I loved that this quilt allows me to completely open the quilt and use it as a blanket. While a sewn-in footbox is better for cold weather, when it comes to a quilt for warmer weather such as this one, it’s much easier to regulate temperature on warm nights with a blanket. I can let my feet or arms out with no effort when I get warm. Plus, the added freedom of movement is a nice luxury. 

Warmth-to-Weight: At 1 lb, 4 oz, this quilt is pretty darn light, and keeps me comfortable down to about 35 degrees. At this weight, it is comparable to similar quilts from other brands. It packs down nice and small too. 

Ember II Cons

Buttons Unsnap Too Easily: As I’ve mentioned before, the snap-on buttons are not very secure. This undermined the functionality of some of the quilt’s best features, so it was a real disappointment. I have quilts from other brands that use snap buttons for straps without this issue. Hopefully in future models of the Ember, Sea to Summit will use some sturdier snaps. 

Cost: With an MSRP of about $329, this quilt isn’t the most expensive quilt on the market, but it’s definitely not the cheapest. There are a variety of similar quilts available for less than $300.

Overall / Value

All in all, this is a solid, lightweight quilt that would be useful on most summer hiking adventures. While warm sleepers might take this along on a thru-hike such as the PCT, I’d personally only trust it for a fast hike of the comparatively warmer Appalachian Trail, and opt for the 20-degree version for the PCT. At retail price, the Ember is a little more expensive than similar quilts, and some of the features don’t work as well as intended. I would recommend this quilt if you can find it on sale. 

Comparable Quilts

Katabatic Flex 30
MSRP: $285+
Weight: 20 ounces

Enlightened Equipment Revelation 30
MSRP: $280+
Weight: 19 ounces

REI Magma Trail Quilt 30
MSRP: $279+
Weight: 19 ounces

Shop the Sea to Summit Ember II Here

**Disclosure: This product was donated for purpose of review


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Comments 6

  • Cam : Aug 25th

    Good review!

    I have this quilt and really like it despite of its limitations. I got it on sale 🙂

    A couple of things worth mentioning: First, the baffles are sewn through. Second, I’m not really sure what you mean by “Given the temperature rating of the quilt, it should be paired with a pad with an R-value between 2.0-3.3” as the comfort rating of this quilt for a woman wearing base layers on a pad with an R-value of 4.0 is 35F. You’re not going to get near the comfort rating on a pad with an R-value of 2.0.

    As a warm sleeping man I’ve had mine down to 25F and was plenty comfortable with a liner, but I don’t reckon I’d be willing to take it any lower than that under planned circumstances.

    • Megan McGowan : Aug 25th

      I’m glad you like the quilt too!

      As for the “given the temperature rating” comment, please allow me to clarify:

      The quilt is rated 30 (or 25-35) so it’s not really suitable for below-freezing weather, except for the warmest of sleepers. And although temperature ratings are tested with a huge 4.0+ R-Value pad, that’s totally overkill.

      According to this R-Value/Temperature comparison:

      A pad with an R-Value of 2.1 is good to 36F, and a pad with an R-Value of 3.2 is good to 23 degrees, so it’s a similar temperature range. It also happens to be typical for most thru-hikers. A NeoAir is 3.2 and a Z-Lite Sol is 2.6. I know some hardcore hikers who go below 2.0, but they also don’t mind sleeping cold every night.

      And no, most backpackers do not attain the assigned comfort rating of their bags and quilts for this exact reason.
      To make it even more confusing, the EN system used for bags doesn’t apply for quilts, so the standards may vary from company to company!

      Also, thanks for pointing out the sewn-through baffles!

      Happy Hiking!


      • Cam : Aug 26th

        I don’t want to argue the point too hard, because we both agree that all the stars have to align to attain the bags comfort rating, but for ground sleepers the usable temperature for a pad of a specific R-value refers to the ground temperature, which in winter is often significantly colder than the air temperature. So if we take your example 2.1 R-value pad, a mythical mannequin sleeper might be a happy camper with an overnight low of 44F, but unhappy at 36F, which is the upper end of the rated “comfort range”.

  • Kurt Eckerblad : Apr 12th

    Thanks for a very good and detailed review


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