BEST USE: Ultralight Backpacking
PERFORMANCE: Warm Weather
WEIGHT: 12oz | 340g
COMPRESSED VOLUME: 1.5 liters
Shipping & Returns
We use climate-neutral shipping with DHL GoGreen.
For orders with a value below 75€ we charge a shipping fee of 4,95€. We do not charge shipping fees for orders with a value over 75€.
All orders received by 12:00 noon on weekdays are usually shipped the same day. Later orders are usually dispatched the following working day.
Delivery time can take up to three working days Germany-wide and up to four working days for orders outside of Germany, and depends on the shipping service provider.
All orders can be returned within 14 days of purchase. However, for the sake of the environment, please make sure to keep returns as low as possible.
The EN Rating scale is a scientific test to determine the warmth of a sleeping bag. The test produces a Lower rating (for male sleepers) and a Comfort rating (for female sleepers). Both are listed in the features table on the product page.
A unisex sleeping bag with a Lower limit of -10°C means a man should be comfortable down to air temperatures of -10°C. The same bag will also have a Comfort limit, in the realm of -3°C, so a woman would be comfortable down to an air temperature of -3°C. These ratings require a sleeping mat with an R-Value appropriate for expected ground temperatures – without this, the sleeping bag itself is unlikely to keep the sleeper warm enough.
A variety of factors impact sleeping bag warmth - the above temperatures are merely guidelines, not guarantees. It’s important to think of a sleeping bag, an appropriately insulating sleeping pad and a liner as a sleep system. For example - if you plan on sleeping in nighttime air temperatures of -3°C, choose a bag with a gender-appropriate rating of -5°C, plus a sleeping mat with an R-Value of 2.5 to 3, and consider a Reactor thermal liner.
The Spark Ultralight Mummy Sleeping Bag Series spans everything from an ultralight down-filled liner, to a mid-winter fast-and-light sleeping bag. Each model uses premium materials and no-frills design to provide cutting-edge performance.
Ultralight does not mean ultra-tight: The Spark mummy sleeping bags are snug but still have adequate wiggle room for the performance-oriented, backcountry user.
Best UseUltralight Backpacking
Comes WithUltra-Sil compression bag and storage cell
InsulationUltra-Dry Down 850+ Loft
Shell FabricUltralight 10D Nylon Shell
Zip OptionsSpark 0-II: Left-side #3 YKK zipper // Spark III-IV: YKK #5
|5°C Regular||5°C Long||-2°C Regular||-2°C Long||-8°C Regular||-8°C Long||-15°C Regular||-15°C Long||Liner Regular||Liner Long|
The highest-lofting down used in any of Sea to Summit’s sleeping bags. 850+ Fill Power indicates that one ounce (30g) of down will re-expand to over 850 cubic inches after compression. Higher loft means that less down can be used to achieve the same temperature rating – important for performance sleeping bags. The loft and down quality/composition are independently tested by the International Down and Feather Laboratory (IDFL) – a copy of the certification is supplied with every Sea to Summit sleeping bag. The down is responsibly sourced and RDS certified and treated with the environmentally-friendly Ultra-Dry Down treatment.
100% of the down used in our sleeping bags and quilts is independently certified to the Responsible Down Standard (RDS). The RDS certifies down against animal welfare requirements and tracks it from the source to the final product. The purchase of RDS certified products demonstrates demand for better animal welfare practices in the down and feather supply chain. Sea to Summit is certified to the RDS. To learn more about RDS visit https://textileexchange.org/standards/responsible-down/
Ultra-Dry Down is a non-PFC treatment hydrophobic treatment applied to the down during down processing. It is not a coating (which would reduce the ability of the down to loft), it comprises of very small particles of a polymer that cause the down clusters / feathers to repel water. Ultra-Dry Down is PFC and PFAS-free. Hydrophobic down is not waterproof; but it absorbs less water than untreated down and dries much more quickly.
Ultra-Dry Down does not affect the loft or lifespan of the down, or its breathability. The treatment will last through at least 20 washings.
Despite being incredibly lightweight, the 10 Denier UL Nylon is down-proof and surprisingly durable. A DWR finish helps to shed external moisture. This fabric is part of the secret to making the Spark and Flame Down Sleeping Bag Series some of the lightest, most packable sleeping bags available today.
Frequently Asked questions
Suitable for cooler temperatures?
Yes. The 5°F or possibly the 18°F will work in late Fall. The Spark 5°F will take you down to winter temperatures when paired with a greater than 3.5 R-Value sleeping mat like the Comfort Light Insulated.
Really suitable as a sleeping bag liner?
Yes. You could use the Spark 50°F, or even the Spark 40°F to boost the performance of a bag for cold-weather use. Adding one of these to a 20°F bag might make more sense than buying a 0°F bag for occasional winter use.
Able to be zipped to another sleeping bag?
No. Even though the 18°F or 5°F have full-length side zippers, they are not designed to be coupled to a sleeping bag with a right zipper (for instance the Flame 18°F or 5°F).
You have more questions?
Check out our FAQ page HERE and discover even more answers about our products.