Temp Rating
Insulation Type
| Shape | Mummy |
|---|---|
| Temp Rating | 15 Degree (F) / -9 Degree (C) |
| Comfort Temp* | 29 Degree (F) - ISO |
| Limit Temp* | 15 Degree (F) - ISO |
| Weight | Regular: 1 lb. 9.7 oz ; Long: 1 lb. 11.7 oz ; Double: 3 lb. 6.4 oz |
| Insulation Type | Down |
| Fill Power | 850-Fill-power goose down |
| Fill Weight | Regular: 1 lb. 0.9 oz ; Long: 1 lb. 3 oz ; Double: 2 lb. 2.7 oz |
| Shoulder Girth | Regular: 61" ; Long: 65" ; Double: 105" |
| Hip Girth | Regular: 61" ; Long: 65" ; Double: 105" |
| Compressed Volume | Regular: 6.8 liters ; Long: 7.6 liters ; Double: 14.3 liters |
| Shell Fabric | 10-Denier nylon |
| Zipper Location | Left |
| Stuff Sack Included | Yes |
| Stuff Sack Volume | Regular: 13 liters ; Long: 13 liters ; Double: 20 liters |
REVIEWS
68 Reviews
Enid H.
Perfect for our Sprinter Van set up as we negotiate the Great Divide Trail!
Sandra B.
It is exactly as advertised and was perfect for what we needed. It is lightweight and compact, didn't take up much space in a pack, while being large enough for my broad shouldered husband and warm enough that he was toasty even when the nights dropped to 5 degrees Celsius (could probably handle colder). (I will definitely consider buying another for myself since I froze with a larger bulkier sleeping bag). It is an expensive purchase, but at least it did the job well.
Kim R.
The bag is light. Not quite as warm as I was hoping. I should've gone with 30 degree bag. I like how it is to pack and how small it packs.
Kilan J.
This is one of the best sleeping bags I’ve ever owned!! 10/10 would recommend. The down is always warm and the ultralight pack ability makes it a go to for any outdoor adventure.
Mark
Thru hiker here who has done the PCT and many treks in Nepal. I purchased the 30 degree bag for my latest PCT hike but have been pretty disappointed. While the size is amazing when compressed the design is missing critical baffles that would stop the down from clumping and exposing your body to nothing but the elements. My bag is comfortable if the outside temp is 55 or better. Anything less and I get cold even in this 30 degree bag. See my photos for what normally happens -- the down shifts in the large baffles leaving nothing between your body and the elements. They need to have smaller baffles that keep the down in place and down't allow it to shift so much. (Down jackets went through this same evolution over the years but SeaToSummit passed on using this knowledge in this bag design. ). I love the company and they've got some excellent gear I use on every trip, but unfortunately this sleeping bag is not one of their best. When I set up camp I thoroughly fluff the bag to help it expand and at that time I work to ensure the down is universally filling each baffle. But during the night with a little tossing and turning the down easily shifts and so I'm left with what you see in the picture -- freezing shoulders or hips because the down shifted. Picture is from inside the bag looking out so you can see how large 12" x 12" spots with no down present create cold spots for my body. I'm 6'0, 160 lbs, and a back/side sleeper. Over 20 years of professional guide experience. I hope Sea To Summit. updates this bag as they're close to having a lightweight bag with great warmth but just missed the ball on this one.
Aaron F.
I've been really impressed with this sleeping bag. It's super compact and packs down small, making it a great choice for bikepacking where every bit of space matters. It replaced my old bulky sleeping bag and freed up a lot of room in my setup. My only suggestion would be to have the zipper run a little farther down the side. I like to kick a leg out while I sleep, and a longer zipper would make that much easier. Overall, it's lightweight, packs incredibly small, and has been a fantastic upgrade. I'd definitely recommend it to anyone looking for a compact sleeping bag for bikepacking or backpacking trips.
John S.
I laughed when I saw the stuff bag for this sleeping bag. I thought it would not be possible to use it. I quickly got used to it and used the sleeping bag on a cross-country motorcycle camping trip. Pack size is as important on a motorcycle as weight is for a backpacker, so this worked out well. The sleeping bag was comfortable and perfect for the season.
Tanner H.
Great bag I used it in a backpacking trip at 9,000 feet in early June I stayed warm and comfortable all night the material is very lightweight so I can tell it would rip easily but otherwise happy with it.
Caleb
I work wildland fire and hunt in the off season. Not to toot my own horn but i get a good sleeping bag when I have one. Comfort and weight are on point. great toe box. I was showing my buddy how light the bag was and he dropped it on a buddy heater. Sea to Summit took care of the whole fix. Absolutely amazing. Simple bag that works as one would want.
Corey L.
I just completed a 750 mile section of the Florida Trail in 10 weeks. I slept in the 30 degree Spark every night. Throughout the 10 weeks there were many nights below freezing with temperatures dipping to the mid 20s. The spark performed marvelously! I even slept without a pad and still was comfortable. I wore multiple layers to sleep only once and frequently used my Poncho as a vapor barrier to help insulate. Other hikers complained about being cold when I was cozy and warm. The only complaint I have about this bag is that with the short zipper it can be a struggle to get in and out of sometimes. But I will take the weight savings that come with that feature over a little wiggling. The dampness of Florida nights did not cause the bag to become wet and my fears of carrying a down bag in a humid environment were conquered. A wonderful product all around.
Tim A.
I got this as a dual purpose bag. First, an ultra light / ultra compact summer bag. Second, to pair with a 25 degree quilt for winter camping. Tried it once in a fire lookout and was too warm (ditched the quilt). Going to put it through its paces over the next year!
Stephen W.
I’m 6'4", about 240 lbs—built more like an aging NFL linebacker than a thru-hiker—and this bag actually fits. Plenty of room to move without cold spots, which matters if you’re a side sleeper like me. It’s warm, comfortable, and feels thoughtfully designed rather than scaled up as an afterthought. Build quality is excellent across the board, and both the storage bag and compression sack are noticeably higher quality than what usually gets tossed in. If you’re bigger, move around in your sleep, and still want real 0-degree performance, this bag delivers.
Brian B.
I tried this sleeping bag all the way down to 5°F with layered clothing, and it did fantastic. Super comfortable. I highly recommend.
Joseph F.
I've used the Sea to Summit Spark 30 on a few trial runs and am impressed with the quality of the bag, compression sack and storage bag! The sleeping bag has been warm and comfortable and packs well. I'm an avid hiker/thru hiker and this bag is a great addition to my gear closet!!!
Kerry W.
Great bag, too small . Insulation fantastic and so light!
Read All Reviews (68)
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