Sea to Summit Spark Sleeping Bag Assessment [2025]

Sharing is caring!

It is a gear evaluation concerning the Sea to Summit Spark Sleeping Baggage in 2025. The sleeping bag evaluation covers the entire Sea to Summit Spark Sleeping Bag Vary however I’ve centered on the Sea to Summit Spark 18F which I’ve extensively used and examined.

The Sea to Summit Spark Sleeping Baggage all use high-quality 850+ Extremely-Dry down, ultralight 10D outer shell cloth coated with a DWR and 10D inside cloth, and so they pack all the way down to a really small pack measurement. There are such a lot of positives to notice concerning the Spark sleeping luggage making them one of many finest light-weight sleeping luggage for 2025.

There have been a few upgrades to this bag in 2019, 2022, and 2024 which have improved points with the bag. These enhancements have additionally made the Spark sleeping luggage even higher.

Maintain studying to seek out out extra.

How We Examined

The Sea to Summit Spark Sleeping Baggage on this evaluation have been extensively evaluated and researched by the knowledgeable writer who has greater than 30 years of expertise in Via-Mountain climbing, Backpacking, and Mountain climbing. He additionally spent a number of years managing a mountain climbing retail retailer and is considered an knowledgeable on this area. It was provided by the producer. They’ve been rigorously examined by the writer in every kind of climate on a number of backpacking journeys. The analysis, testing, and expertise of the writer have mixed to current this trustworthy and unbiased evaluation. Learn the Assessment Coverage for additional particulars.

Sea to Summit Spark Ultralight Sleeping Bag Specs 2025

Sea to Summit Spark 45F Specs

Weight: 12.8 oz / 363 grams
Down Fill: 5.3 oz / 150 grams
Sleeping Bag Cloth Weight (with out down): 7.5 oz / 213 grams
Down fill energy: 850+
Extremely-Dry Down: Sure
Complete down loft in cubic inches: 4,505 cubic inches of down loft
Zip: Sure, 1/2 size YKK zips
Draft Tube on Zip: Sure
Hood: Sure
Stuff Sack: Sure, a compression stuff sack
Stuff Sack: XXXS
Stuff Sack Compressed Quantity: 2.4L

Sea to Summit Spark 30F Specs

Weight: 1lb 1.4 oz / 493 grams
Down Fill: 9.3 oz / 265 grams
Sleeping Bag Cloth Weight (with out down): 8.1 oz / 228 grams
Down fill energy: 850+
Extremely-DryDown: Sure
Complete down loft in cubic inches: 7,905 cubic inches of down loft
Zip: Sure, 1/2 size YKK zips
Draft Tube on Zip: Sure
Hood: Sure
Stuff Sack: Sure, a compression stuff sack
Stuff Sack measurement: XXS
Stuff Sack Compressed Quantity: 4.3L

Sea to Summit Spark 15F Specification

Weight: 1lb 11.7 oz / 730 grams
Down Fill: 15.2 oz / 480 grams
Sleeping Bag Cloth Weight (with out down): 12.5 oz / 250 grams
Down fill energy: 850+
Extremely-DryDown: Sure
Complete down loft in cubic inches: 12,920 cubic inches of down loft
Zip: Sure, full size YKK zips
Draft Tube on Zip: Sure
Hood: Sure
Stuff Sack: Sure, a compression stuff sack
Stuff Sack measurement: XS
Stuff Sack Compressed Quantity: 6.8L

Sea to Summit Spark 0F Specification

Weight: 2lb 7.3 oz / 1113 grams
Down Fill: 29.6 oz / 840 grams
Sleeping Bag Cloth Weight (with out down): 9.7 oz / 273 grams
Down fill energy: 850+
Extremely-DryDown: Sure
Complete down loft in cubic inches: 25,160 cubic inches of down loft
Zip: Sure, full-length YKK zips
Draft Tube on Zip: Sure
Hood: Sure
Stuff Sack: Sure, a compression stuff sack
Stuff Sack measurement: S
Stuff Sack Compressed Quantity: 9.9L

STS Spark Ultralight Sleeping Baggage

When Sea to Summit first launched the ultralight Spark Sleeping Bag vary it grew to become successful as they chased the ultralight sleeping bag market. As soon as upon a time, ultralight backpackers and thru-hikers have been seen as freaks who compromised sturdiness and security whereas chasing decrease ounces and grams. Now ultralight is mainstream and accessible to all.

Latest upgrades adjustments to among the zips on the baggage, vertical baffles to forestall down shift whereas tossing and turning at evening, and an improved PFC-free DWR end. All of those enhancements have elevated the power of the bag to maintain you heat at evening, elevated the performance of the baggage, and diminished the environmental influence of the bag. Top-of-the-line upgrades with the most recent mannequin is the Quiltlock System which permits a Sea to Summit Quilt to connect to the sleeping bag. This might let you connect them collectively and lengthen your sleeping bag vary into a lot colder temperatures and in some instances you could not want a separate Winter Sleeping Bag.

They’ve retained the beneficiant inside sizing and dedication to having the temperatures of the baggage independently examined to EN requirements.

Word: In March 2022 a brand new sleeping bag customary, ISO 23537, was launched as the brand new sleeping bag requirements. Sea to Summit has knowledgeable me that they are going to be testing all their luggage to this customary very quickly. I like this dedication to making sure the sleeping bag rankings are independently examined somewhat than a finest guess on how heat you ought to be like some corporations do.

Down sort / fill energy

The Sea to Summit Spark is stuffed with 850+ Extremely-DryGoose Down in 2025. That is the top quality down used on any Sea to Summit Sleeping Bag. It isn’t solely light-weight nevertheless it additionally has good water resistance qualities because it makes use of the water repellent Extremely-Drydown.

Whenever you buy a Sea to Summit Bag you’re going to get a certificates from the Worldwide Down Feather Laboratory (IDFL). This certificates will state precisely what Responsibly Sourced Down was utilized in your Sea to Summit Ember sleeping bag.

After I opened my new sleeping bag I used to be stunned to study that my down sleeping bag had a barely larger fill Extremely-Drydown. The said 850+ down is the minimal customary that Sea to Summit has dedicated to placing in your Spark Bag. Generally that batch could also be a bit of larger however by no means decrease. Only a small however spectacular function from Sea to Summit

Development

Let’s check out how the sleeping bag is made with options such because the Inside and Outer Shell materials, zippers, baffles, draft tubes, hood, and climate resistance.

Outer Shell cloth

The exterior face cloth of the Sea to Summit Spark sleeping bag is made utilizing a ten Denier Ripstop Nylon which is coated with a brand new PFC-free DWR coating to forestall drops of water from coming into the bag. The material is so mild and so skinny it’s virtually see-through, particularly whenever you maintain it as much as the sunshine.

When testing the spark sleeping bag I dropped a big quantity of water on the outer cloth to check the water resistance of the material and the water beaded properly and ran off the material. I’m a fan of this ultralight outer cloth and the brand new DWR coating.

Additionally good to know if water did in some way enter and get into the down nearly all of it won’t be absorbed because of using the high-quality Extremely-Drydown.

Inside cloth

The Sea to Summit Spark sleeping bag makes use of a light-weight 10D inside cloth. The ten Denier cloth shouldn’t be solely ultralight but in addition resistant to ripping.

I did attempt to rip the material with my palms, Arnold Schwarzenegger model, and it was powerful sufficient to not rip. Or possibly I’m simply not very sturdy!

Climate resistance

As talked about above, I did drop water on the outer face cloth to check the water resistance and high quality of the DWR coating. I can verify it can present a good degree of water resistance that’s a minimum of equal to or higher than all of the competitors within the Ultralight Sleeping Bag market.

The Sea to Summit Spark is nice sufficient to sleep exterior beneath the celebs when condensation comes down in a single day.

Disclaimer: I don’t advocate that you simply pour an entire bottle of water over your sleeping bag to check its water resistance.

Baffles

A few years in the past the Spark vary modified to vertical baffles within the torso space to forestall down shift whereas sleeping at evening, particularly good in case you are a slide sleeper. The decrease area and backside facet of the bag use a sewn-through design to maintain weight to a minimal.

The hotter Spark 45F and Spark 30F use full field baffles to fill extra down into the bag for larger heat. Whether or not you need weight-saving or heat, the baffle design has you lined.

My solely critique was the quantity of down in every baffle may have been a bit of larger to forestall down clumping. After some time the down will begin to clump a bit of, this occurs to each sleeping bag. Slight overfill will cut back the clumping impact. Washing the bag will repair the clumping points on a closely used sleeping bag.

Zips and Draft Tube

The Spark collection options both a full zip or 1/2 size zip. The 45F and 30F function 1/2 size top-of-the-range YKK #3 zips and a draft tube to maintain within the heat. The 15F and 0F function full-length YKK zips with a zipper draft tube.

I attempted my finest to destroy the zip and tried to snag it on the interior draft collar. All makes an attempt failed. The zip and draft collar are well-positioned and stop snagging. This is a matter on many sleeping luggage however not the Spark sleeping bag.

The zip can snag when attempting to open the bag. It’s going to snag for most individuals once they attempt to open the bag. There’s a quirk with virtually all YKK zips on sleeping luggage. Should you attempt to open them at an angle they are going to stick. As soon as you recognize this, and alter the way you open the sleeping bag, one can find it really works nice.

General, the zips and draft tubes do a great job and there may be not a lot that may be faulted.

Hood

The hood on the Spark is nice and includes a full collar the entire method round. There’s an outsized drawcord toggle on the right-hand facet which is a bit of greater than it must be. The toggle might be cinched tight to shut off many of the hood and go away solely the nostril and mouth in place to get contemporary air on these very chilly nights.

The neck and hood collars may very well be a bit of greater and will have extra overfilled for higher warmth retention. In my expertise the hood collar and neck collar areas of sleeping luggage are the primary locations to get soiled from physique oils and sweat which ends up in the down turning into extra compressed and clumped, making them much less environment friendly at preserving you heat.

After I examined the Sea to Summit Spark I spent quite a lot of time sleeping on my facet and rolling over rather a lot. The hood did a great job preserving within the heat.

As talked about above, possibly a bit extra overfill within the hood and draft collars can be a great enchancment.

Stuff Sack

The usual Stuff Sack provided with the Spark sleeping bag is nice and there’s no want for anybody to think about upgrading to anything. It’s light-weight and might be compressed with the facet straps to compress the baggage into a really small measurement. The Spark is without doubt one of the most compressible sleeping luggage in its class of ultralight sleeping luggage.

Compression

As talked about above the stuff sac will compress the bag to a smaller measurement. Discuss with the Specification chart for detailed comparisons.

Packability

The Sea to Summit Spark collection is presumably essentially the most packable of all of the sleeping luggage within the ultralight class.

Consolation

The inner sizing of the Spark sleeping luggage has elevated in recent times. Though they’re a basic mummy model of the sleeping bag, they’ve been upgraded to expedition sizing which permits most customers to have the ability to put on a down jacket, down pants, or down booties contained in the sleeping bag with ease.

When testing the bag I wore my expedition-weight down jacket contained in the bag and I nonetheless had loads of room to toss and switch with out feeling constricted. When sleeping on my again or facet I discovered it to be comfy and in a position to preserve me heat with no points to report.

An inexpensive method to flip your bag right into a winter sleeping bag is to make use of one other sleeping bag or quilt with any of those luggage. The beneficiant sizing will let you use one sleeping bag inside one other, thus turning your 3-season sleeping bag right into a 4-season winter sleeping bag at a less expensive value.

Heat

When testing the bag I discovered the temperature score to be true to these said by Sea to Summit. Every sleeping bag model from the Sp1 to the Sp4 has been examined to EN requirements so you may relaxation assured that the sleeping bag will preserve you heat on the temperatures as reported.

I’m usually a chilly sleeper except I eat a really heavy meal earlier than going to mattress (which might preserve you hotter at evening). I’m a facet sleeper on the whole and I discovered the bag to work nicely when sleeping on my facet or again.

It’s tremendous vital to notice that there are 3 temperature rankings listed on every sleeping bag.

Consolation Ranking

The Consolation Ranking is an important score as that is the temperature at which you can be heat and may sleep nicely. Sadly, the sleeping bag trade as an entire fails to make use of this score for advertising causes. However use this as your base for what bag will preserve you heat at what temperature.

That is normally the temperature at which a lady will sleep nicely with out being chilly.

Restrict Ranking

The Restrict Ranking is utilized by virtually all sleeping bag producers because the temperature score for the sleeping bag. Few individuals will get a great evening’s sleep on the restrict score except you recognize your physique nicely sufficient to know you’re a heat sleeper. I do know myself nicely sufficient to know I’m normally midway between the Consolation and Restrict Ranking for my very own private score on how heat I will probably be at evening inside a bag.

That is normally the temperature score {that a} male, curled up on his facet, will sleep. Most individuals will really feel chilly and never sleep nicely when sleeping on the restrict score temperatures.

Excessive Restrict

The Excessive Restrict is the restrict inside which individuals won’t die from hypothermia or excessive chilly. You might be assured that in case you use the bag on the Excessive Restrict you’ll stay awake in any respect. If going into the Excessive Restrict you’ll want to get a Thermal Sleeping Bag Liner and even higher improve to a 4 Season Winter Sleeping Bag.

Dimension

As talked about above the sleeping bag is comfy and designed as an expedition measurement. This lets you put on layers of clothes if wanted whereas contained in the sleeping bag. Due to this fact, the Spark Sleeping luggage have greater inside dimensions than most ultralight mummy-style sleeping luggage.

Caring to your Spark Sleeping Bag

When you’ve a high-quality sleeping bag it’s price taking care to take care of it. Top-of-the-line issues you are able to do is put on clear backpacking base layers to mattress to forestall sweat, filth, and physique oil from penetrating the liner of the sleeping bag. You can even use a sleeping bag liner to maintain it clear.

Tips on how to retailer your Spark sleeping bag

The Sea to Summit Spark comes with a Lofting bag included together with your bag. The lofting bag shouldn’t be as giant as I would love. A few years in the past Sea to Summit Sleeping Baggage got here with a really giant cotton lofting bag. I might have preferred to see a bigger lofting bag a minimum of twice the scale of the one provided.

Like most individuals, I typically go weeks and months between mountain climbing journeys or bikepacking journeys into the backcountry. Whereas not utilizing the sleeping bag I might like to have it saved in a big lofting bag. Perhaps that’s one thing that may enhance sooner or later. Having mentioned that, the lofting bag is such a minor grievance that I can overlook this when taking into consideration the general high quality of the sleeping bag and all the pieces else provided with the bag.

Tips on how to wash your Spark Sleeping Bag

Over time the sleeping bag will lose a little bit of its loft and you could begin to complain that the bag is inferior to it was. Perhaps it’d begin to have some funky smells that appear to be a cross between a sweaty fitness center and an unwashed homeless particular person. If this happens it’s time to wash the sleeping bag. I wrote an article on how to do that so check out Tips on how to Wash a Down Sleeping Bag, for additional particulars on learn how to wash your bag.

Value

The Sea to Summit Spark is a premium Sleeping Bag at a premium value. Having mentioned that, they don’t value as a lot as among the different premium ultralight sleeping luggage available on the market for the time being. The Spark Vary sits on the larger finish of the value vary in comparison with the rivals however that larger value comes with typically higher availability.

No want to affix a waitlist or anticipate the baggage to be made like some ultralight corporations.

Sea to Summit Spark Vs The Relaxation

How does the Sea to Summit Spark examine to different Sleeping Baggage within the ultralight class in 2025. Take a look at my full comparability evaluation of the Sea to Summit Spark and all of the Finest Ultralight Sleeping Baggage 2025.

Finest Suited Use

The Spark Sleeping Baggage can be excellent for anybody who’s sleeping in temperatures above freezing or beneath within the case of the Spark 0F. The next varieties of journeys can be excellent for this bag.

• Summer time mountain climbing within the Rockies or Sierra or North America. Or into the Spring and Fall if utilizing the hotter Spark 15F and Spark 0F.
• Summer time mountain climbing within the Alps in Europe or mountain climbing the Camino. The hotter luggage will probably be nicely suited to three season journeys in most locations.
• Summer time mountain climbing and 3-season mountain climbing in Australia and New Zealand in most areas.
• Summer time journeys in South America together with Patagonia so long as the nighttime temperatures are above freezing. Chances are you’ll want the Spark 0F or one thing with extra insulation if heading to the Excessive Andes of Bolivia, Peru, and Ecuador.

Conclusion

The Sea to Summit Spark is finest suited to anybody wanting a high-quality ultralight sleeping bag. The temperature score for this bag is true to the specification in my view and primarily based on my use of the sleeping bag.

If you would like a sleeping bag for the summer season months and into the shoulder season for hotter climates then that is for you.

In terms of enhancements, I want to see a lighter-weight cinch chord on the hood, overstuffing down on the hood, collar, and neck draft tubes, and a bigger lofting bag.

I’m wondering if they’re contemplating utilizing the next loft Ultrdry down sooner or later. Some producers at the moment are utilizing 900+ Extremely-Dry and 950+ loft. When you get that prime on the loft score the down turns into a bit of extra delicate and must be taken care of nicely by the consumer. Simply my ideas.

General, the Sea to Summit Spark vary of sleeping luggage is considered one of my all-time favourite sleeping luggage in 2025. There’s little to fault, and people faults are so small that it isn’t sufficient to make the bag something lower than probably the greatest available on the market.

Steadily Requested Questions

Sharing is caring!