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Sea to Summit Spark Ultralight Down Sleeping Bag

4.5 4.5 out of 5 stars 186 ratings
Price: $549.00 $999.00 Free Return on some sizes and colors

15-degree
Brand Sea to Summit
Occupancy 2 Person
Shape Mummy
Seasons 7 Seasons
Temperature Rating 15°F
Age Range (Description) Adult
Sport Backpacking
Material Nylon
Fill Material Down
Product Dimensions 83.1"L x 52.8"W

About this item

  • Nylon
  • 15-degree Fahrenheit (-9-degree Celsius) ultralight down sleeping bag for 2-season backpacking, bike packing, and touring
  • High-loft 850+ fill power down insulation (Responsible Down Standard certified) with a non-PFC Ultra-Dry down treatment to improve reaction to moisture, retaining loft and performance
  • Ultralight 10D shell with PFC-free DWR keeps the hood and footbox highly water resistant; breathable 10D nylon liner provides all-night comfort
  • Contoured mummy shape provides adequate room for a natural sleeping position; YKK #5 zippers provide reliable, snag-free operation
  • Full box baffles for maximize warmth; Sea to Summit Guarantee is offered for the Lifetime of this product
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Top Brand: Sea to Summit

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Product Description

The Sea to Summit Spark 15-Degree Ultralight Down Sleeping Bag is a technical down bag, engineered for warmth at the lightest weight and smallest compressed size. Ideal for backpacking, bike packing, and touring, the mummy style keeps the cold out and the warmth in. High-loft, 850+ fill power down insulation (Responsible Down Standard certified) is treated with proprietary non-PFC Ultra-Dry Down treatment to improve reaction to moisture and retain loft and performance in rugged conditions. The contoured mummy shape provides adequate room for a natural sleeping position and full box baffles maximize warmth. The ultralight 10D nylon shell is treated with PFC-free DWR and offers cutting-edge packability and warmth. The 10D liner fabric allows the bag to breathe and remain comfortable. A YKK #5 zipper operates snag-free. The Sea to Summit Spark 15-Degree Ultralight Down Sleeping Bag is available in three sizes: Regular (max user height of six feet), Long (max user height of six feet six inches), and Double (max user height of six feet six inches). It includes an Ultra-Sil compression sack and storage cube. Sea to Summit products are guaranteed against defects in materials or workmanship for the lifetime of the product.

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Customer reviews

4.5 out of 5 stars
4.5 out of 5
186 global ratings

Customers say

Customers like the weight, quality and versatility of the sleeping bag. They mention it's very light, compact and portable. Some say it'll be perfect for summer backpacking, camping and travel. They also appreciate the warmth.

AI-generated from the text of customer reviews

9 customers mention9 positive0 negative

Customers like the weight of the sleeping bag. They say it's very light, compact, and portable. Some mention that it'll fit into a small sack.

"This bag is well made and packs easily into a small sack...." Read more

"...This bag packs super small and is light weight. Evening temps were in the mid 50's and this bag kept me plenty warm." Read more

"Great bag for summer trips. Super light and compact. Not as fragile as it looks." Read more

"very warm. works great. very light and portable." Read more

4 customers mention4 positive0 negative

Customers are satisfied with the quality of the sleeping bag. They mention that it is not as fragile as it looks.

"This bag is well made and packs easily into a small sack...." Read more

"I returned for the 8 degree one but it seems like a great quality" Read more

"Great bag for summer trips. Super light and compact. Not as fragile as it looks." Read more

"quality product..." Read more

3 customers mention3 positive0 negative

Customers like the versatility of the sleeping bag. They mention it's perfect for summer backpacking, well suited to camping in the smoky mountains over Labor Day, and a great product for travel.

"Great bag for summer trips. Super light and compact. Not as fragile as it looks." Read more

"great product for travel." Read more

"...It was well suited to camping in the smoky mountains over Labor Day...." Read more

3 customers mention3 positive0 negative

Customers like the warmth of the sleeping bag. They mention it's super lightweight and warm.

"...Evening temps were in the mid 50's and this bag kept me plenty warm." Read more

"very warm. works great. very light and portable." Read more

"I like this bag because it’s super lightweight and warm. However, the stuff sack broke IMMEDIATELY, so now I’m not able to pack it down as small...." Read more

Top reviews from the United States

William M.
5.0 out of 5 stars great sleeping bag for warmer temperatures
Reviewed in the United States on November 21, 2022
Size: RegularStyle: 28-degreeVerified Purchase
This bag is well made and packs easily into a small sack. I often use it for sleeping at my workplace and the cube storage bag is perfect for my office locker! So far I have only used it a 70F and I am very comfortable sleeping with the zipper down. I like the look and feel of it. I generally only use sleeping bags down to about 20F above their rating and this feel like I would be comfortable down to about 50F zipped up.
2 people found this helpful
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Frank
5.0 out of 5 stars Phenom weight/comfort for those lightening load
Reviewed in the United States on March 17, 2024
Size: RegularStyle: 40-degreeVerified Purchase
70 ish retired Vet, 2k mile AT solo section hiker who is very load conscious. For non-winter hikes, I replaced my favorite, 10 yr old Sierra Designs Ultralumina with this product. Reduced sleep system by 1lb without loss of comfort/warmth. This product gives me better capability to complete long hikes as I am experiencing getting older/facing reality about aging. Good value, imo.
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tmarine
5.0 out of 5 stars This is really compact
Reviewed in the United States on March 21, 2024
Size: RegularStyle: 40-degreeVerified Purchase
I used this back on a 9-day backpacking trip. This bag packs super small and is light weight. Evening temps were in the mid 50's and this bag kept me plenty warm.
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Mike&Jenn
4.0 out of 5 stars Light but nice
Reviewed in the United States on February 11, 2023
Size: RegularStyle: 18-degreeVerified Purchase
I returned for the 8 degree one but it seems like a great quality
2 people found this helpful
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adam s helmig
5.0 out of 5 stars Perfect for summer backpacking
Reviewed in the United States on October 14, 2019
Size: LongStyle: 50-degreeVerified Purchase
Great bag for summer trips. Super light and compact. Not as fragile as it looks.
2 people found this helpful
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Cesar Serrano
5.0 out of 5 stars quality product
Reviewed in the United States on November 19, 2019
Size: LongStyle: 40-degreeVerified PurchaseEarly Reviewer Rewards(What's this?)
very warm. works great. very light and portable.
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DCS
5.0 out of 5 stars good for travel
Reviewed in the United States on October 6, 2019
Size: LongStyle: 50-degreeVerified PurchaseEarly Reviewer Rewards(What's this?)
great product for travel.
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Lacey
3.0 out of 5 stars Ultralight but hardly a comfort of 50°
Reviewed in the United States on August 22, 2023
Size: RegularStyle: 50-degreeVerified Purchase
Broke down and bought this because it was the lightest bag I could find. I used it on a 6-day backpacking trip on Isle Royale, in Michigan in August.
It packs down to the size of a water bottle or smaller and would be a great summer bag in warmer climates. I found it didn't keep me warm all night long, even with base layers and socks on I was still cold in the mid 50s, low 60s. I run a little colder than most so maybe this bag would work if you run warm or have a little more insulation on you. I debated returning it but decided to keep it because it's so lightweight and could be used for a warmer trip in the future.
One person found this helpful
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Top reviews from other countries

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fabrizio morici
5.0 out of 5 stars Ottimo
Reviewed in Italy on March 14, 2024
Size: RegularStyle: 40-degreeVerified Purchase
Ottimo
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Amazon Kunde
5.0 out of 5 stars Tolle Wärmeleistung.
Reviewed in Germany on February 18, 2024
Size: RegularStyle: 28-degreeVerified Purchase
Mein erster Daunenschlafsack. Zwar bin ich noch nicht an die Grenz-Temperatur gekommen, aber was dieser kleine Schlafsack mit dem geringen Gewicht leistet, ist wirklich top.
Grenzwerte und Langlebigkeit kann ich noch nicht bewerten.
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Amazon Kunde
5.0 out of 5 stars Bester Schlafsack für eine Hüttentour
Reviewed in Germany on September 26, 2023
Size: LongStyle: 50-degreeVerified Purchase
Das ist mit Abstand der beste Schlafsack den ich je hatte. Alleine die Packmaße sind ein Traum 150g schwer und die Abmaße von einem kleinen Seifenspender.
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Jan Schaab
1.0 out of 5 stars Defekter Reißverschluss. Offenbar wurde B-Ware als neuwertig verkauft.
Reviewed in Germany on May 30, 2023
Size: LongStyle: 18-degreeVerified Purchase
Schnelle Lieferung. Gute verpackt. Leider hatte der Reißverschluss einen Defekt: War nicht lang, asymmetrisch und nicht abschliessend überdeckt eingenäht. Öffnen war möglich. Schliessen war nicht normal möglich, hat mehrere Minuten gedauert, womöglich funktioniert es nach kurzer Zeit gar nicht mehr - völlig praxisuntauglich. Beschädigte Ware als neu deklariert und verkauft.
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Jan Schaab
1.0 out of 5 stars Defekter Reißverschluss. Offenbar wurde B-Ware als neuwertig verkauft.
Reviewed in Germany on May 30, 2023
Schnelle Lieferung. Gute verpackt. Leider hatte der Reißverschluss einen Defekt: War nicht lang, asymmetrisch und nicht abschliessend überdeckt eingenäht. Öffnen war möglich. Schliessen war nicht normal möglich, hat mehrere Minuten gedauert, womöglich funktioniert es nach kurzer Zeit gar nicht mehr - völlig praxisuntauglich. Beschädigte Ware als neu deklariert und verkauft.
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One person found this helpful
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Stefano
5.0 out of 5 stars Sacco a pelo in piuma
Reviewed in Italy on December 19, 2023
Size: RegularStyle: 28-degreeVerified Purchase
Molto caldo e leggerissimo. Nella confezione e prevista una sacca areata per non rovinare la piuma interna
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