This can be a gear overview concerning the Sea to Summit Spark Sleeping Baggage in 2025. The sleeping bag overview 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 material coated with a DWR and 10D internal material, and so they pack right down to a really small pack dimension. There are such a lot of positives to notice concerning the Spark sleeping luggage making them one of many greatest 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.
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How We Examined
The Sea to Summit Spark Sleeping Baggage on this overview have been extensively evaluated and researched by the knowledgeable creator who has greater than 30 years of expertise in Through-Mountaineering, Backpacking, and Mountaineering. He additionally spent a number of years managing a mountain climbing retail retailer and is thought to be an knowledgeable on this subject. It was equipped by the producer. They’ve been rigorously examined by the creator in every kind of climate on a number of backpacking journeys. The analysis, testing, and expertise of the creator have mixed to current this sincere and unbiased overview. 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 Material 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 Material 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 dimension: 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 Material 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 dimension: 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 Material 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 dimension: 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 a hit as they chased the ultralight sleeping bag market. As soon as upon a time, ultralight backpackers and thru-hikers had 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 a number of the zips on the baggage, vertical baffles to stop down shift whereas tossing and turning at night time, and an improved PFC-free DWR end. All of those enhancements have elevated the power of the bag to maintain you heat at night time, elevated the performance of the baggage, and decreased the environmental affect of the bag. Top-of-the-line upgrades with the newest mannequin is the Quiltlock System which permits a Sea to Summit Quilt to connect to the sleeping bag. This might mean you can connect them collectively and prolong your sleeping bag vary into a lot colder temperatures and in some circumstances you could not want a separate Winter Sleeping Bag.
They’ve retained the beneficiant inner sizing and dedication to having the temperatures of the baggage independently examined to EN requirements.
Observe: 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 fairly than a greatest guess on how heat try to be like some firms do.
Down sort / fill energy
The Sea to Summit Spark is full of 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 however it additionally has good water resistance qualities because it makes use of the water repellent Extremely-Drydown.
If you buy a Sea to Summit Bag you’ll 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 increased fill Extremely-Drydown. The acknowledged 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 increased however by no means decrease. Only a small however spectacular characteristic from Sea to Summit
Building
Let’s check out how the sleeping bag is made with options such because the Interior and Outer Shell materials, zippers, baffles, draft tubes, hood, and climate resistance.
Outer Shell material
The exterior face material 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 stop drops of water from getting into the bag. The material is so gentle and so skinny it’s virtually see-through, particularly once you maintain it as much as the sunshine.
When testing the spark sleeping bag I dropped a big quantity of water on the outer material 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 material 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.
Interior material
The Sea to Summit Spark sleeping bag makes use of a light-weight 10D internal material. The ten Denier material just isn’t solely ultralight but additionally resistant to ripping.
I did attempt to rip the material with my fingers, Arnold Schwarzenegger fashion, and it was powerful sufficient to not rip. Or possibly I’m simply not very robust!
Climate resistance
As talked about above, I did drop water on the outer face material to check the water resistance and high quality of the DWR coating. I can verify it’s going to present a good stage of water resistance that’s at the least equal to or higher than all of the competitors within the Ultralight Sleeping Bag market.
The Sea to Summit Spark is sweet sufficient to sleep exterior below the celebs when condensation comes down in a single day.
Disclaimer: I don’t suggest that you simply pour a complete 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 stop down shift whereas sleeping at night time, particularly good if you’re a slide sleeper. The decrease area and backside aspect 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 better 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 increased to stop down clumping. After some time the down will begin to clump a bit, this occurs to each sleeping bag. Slight overfill will scale back the clumping impact. Washing the bag will repair the clumping points on a closely used sleeping bag.
Zips and Draft Tube
The Spark sequence options both a full zip or 1/2 size zip. The 45F and 30F characteristic 1/2 size top-of-the-range YKK #3 zips and a draft tube to maintain within the heat. The 15F and 0F characteristic full-length YKK zips with a zipper draft tube.
I attempted my greatest 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’ll snag for most individuals once they attempt to open the bag. There’s a quirk with virtually all YKK zips on sleeping luggage. If you happen to try to open them at an angle they may stick. As soon as this, and alter the way you open the sleeping bag, you’ll discover it really works nice.
General, the zips and draft tubes do job and there may be not a lot that may be faulted.
Hood
The hood on the Spark is sweet and contains a full collar the entire means round. There may be an outsized drawcord toggle on the right-hand aspect which is a bit larger than it must be. The toggle could be cinched tight to shut off a lot 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 larger 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 results in the down changing into extra compressed and clumped, making them much less environment friendly at holding you heat.
After I examined the Sea to Summit Spark I spent quite a lot of time sleeping on my aspect and rolling over lots. The hood did job holding within the heat.
As talked about above, possibly a bit extra overfill within the hood and draft collars can be enchancment.
Stuff Sack
The usual Stuff Sack equipped with the Spark sleeping bag is sweet and there’s no want for anybody to think about upgrading to anything. It’s light-weight and could be compressed with the aspect straps to compress the baggage into a really small dimension. The Spark is likely 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 dimension. Discuss with the Specification chart for detailed comparisons.
Packability
The Sea to Summit Spark sequence is presumably probably the most packable of all of the sleeping luggage within the ultralight class.
Consolation
The inner sizing of the Spark sleeping luggage has elevated lately. Though they’re a basic mummy fashion 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 aspect I discovered it to be comfy and in a position to maintain me heat with no points to report.
An affordable 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 mean you can 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 worth.
Heat
When testing the bag I discovered the temperature ranking to be true to these acknowledged by Sea to Summit. Every sleeping bag fashion from the Sp1 to the Sp4 has been examined to EN requirements so you’ll be able to relaxation assured that the sleeping bag will maintain 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 may maintain you hotter at night time). I’m a aspect sleeper basically and I discovered the bag to work properly when sleeping on my aspect or again.
It’s tremendous necessary to notice that there are 3 temperature rankings listed on every sleeping bag.
Consolation Ranking
The Consolation Ranking is an important ranking as that is the temperature at which you can be heat and will sleep properly. Sadly, the sleeping bag trade as a complete fails to make use of this ranking for advertising and marketing causes. However use this as your base for what bag will maintain you heat at what temperature.
That is normally the temperature at which a girl will sleep properly with out being chilly.
Restrict Ranking
The Restrict Ranking is utilized by virtually all sleeping bag producers because the temperature ranking for the sleeping bag. Few folks will get night time’s sleep on the restrict ranking except your physique properly sufficient to know you’re a heat sleeper. I do know myself properly sufficient to know I’m normally midway between the Consolation and Restrict Ranking for my very own private ranking on how heat I shall be at night time inside a bag.
That is normally the temperature ranking {that a} male, curled up on his aspect, will sleep. Most individuals will really feel chilly and never sleep properly when sleeping on the restrict ranking temperatures.
Excessive Restrict
The Excessive Restrict is the restrict inside which individuals won’t die from hypothermia or excessive chilly. You could be assured that when you use the bag on the Excessive Restrict you’ll stay awake in any respect. If going into the Excessive Restrict you should definitely 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 dimension. This lets you put on layers of clothes if wanted whereas contained in the sleeping bag. Subsequently, the Spark Sleeping luggage have larger inner dimensions than most ultralight mummy-style sleeping luggage.
Caring in your Spark Sleeping Bag
When you could have a high-quality sleeping bag it’s value 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 stop sweat, filth, and physique oil from penetrating the liner of the sleeping bag. You can too use a sleeping bag liner to maintain it clear.
Methods to retailer your Spark sleeping bag
The Sea to Summit Spark comes with a Lofting bag included along with your bag. The lofting bag just isn’t as massive as I would really like. A few years in the past Sea to Summit Sleeping Baggage got here with a really massive cotton lofting bag. I might have preferred to see a bigger lofting bag at the least twice the scale of the one equipped.
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. Possibly that’s one thing that may enhance sooner or later. Having mentioned that, the lofting bag is such a minor criticism that I can overlook this when making an allowance for the general high quality of the sleeping bag and every part else equipped with the bag.
Methods 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 once. Possibly it would begin to have some funky smells that appear to be a cross between a sweaty health club and an unwashed homeless individual. If this happens it’s time to wash the sleeping bag. I wrote an article on how to do that so check out Methods to Wash a Down Sleeping Bag, for additional particulars on how one can wash your bag.
Worth
The Sea to Summit Spark is a premium Sleeping Bag at a premium worth. Having mentioned that, they don’t price as a lot as a number of the different premium ultralight sleeping luggage available on the market for the time being. The Spark Vary sits on the increased finish of the worth vary in comparison with the opponents however that increased worth comes with usually higher availability.
No want to hitch a waitlist or look ahead to the baggage to be made like some ultralight firms.
Sea to Summit Spark Vs The Relaxation
How does the Sea to Summit Spark evaluate to different Sleeping Baggage within the ultralight class in 2025. Take a look at my full comparability overview of the Sea to Summit Spark and all of the Greatest Ultralight Sleeping Baggage 2025.
Greatest Suited Use
The Spark Sleeping Baggage can be excellent for anybody who’s sleeping in temperatures above freezing or under within the case of the Spark 0F. The next sorts 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 shall be properly 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. It’s possible 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 greatest suited to anybody wanting a high-quality ultralight sleeping bag. The temperature ranking for this bag is true to the specification for my part and primarily based on my use of the sleeping bag.
In order for you a sleeping bag for the summer time months and into the shoulder season for hotter climates then that is for you.
With regards to enhancements, I wish 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 ponder if they’re contemplating utilizing a better loft Ultrdry down sooner or later. Some producers at the moment are utilizing 900+ Extremely-Dry and 950+ loft. When you get that top on the loft ranking the down turns into a bit extra delicate and must be taken care of properly by the person. Simply my ideas.
General, the Sea to Summit Spark vary of sleeping luggage is certainly one of my all-time favourite sleeping luggage in 2025. There may be little to fault, and people faults are so small that it isn’t sufficient to make the bag something lower than the most effective available on the market.
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Steadily Requested Questions
Are Sea to Summit Sleeping Baggage any good?
Sea to Summit Sleeping Baggage are a number of the highest quality and lightest weight obtainable. The Spark, Flame, Ember, and Alpine Sequence are significantly good sleeping luggage.
Does Sea to Summit Sleeping Baggage use Responsibly Sourced Down?
Sure, All of the down sleeping luggage from Sea to Summit are ethically sourced down that may be traced as responsibly sourced.
BikeHikeSafari Gear Assessment Course of
The creator, Brad McCartney from BikeHikeSafari is a small impartial adventurer and outside gear tester who owns and runs BikeHikeSafari.com.
BikeHikeSafari just isn’t half of a giant weblog community and is proudly impartial. All evaluations on this website are impartial and sincere gear evaluations of outside merchandise by the creator.
The creator, Brad McCartney is a really skilled triple crown thru-hiker, adventurer, and bike tourer having spent 1000s of nights sleeping in a tent and sleeping bag (Learn extra). He was a supervisor of an out of doors retail retailer and may be very skilled in what’s necessary when utilizing and testing gear for evaluations like this.
BikeHikeSafari won’t ever obtain any cash for evaluations and they don’t settle for sponsored evaluations on this web site. All of the feedback concerning the gear evaluations are from the creator primarily based on his years of expertise. Hope this impartial overview was useful for you.
