The Sea-to-Summit Spark 1 (40-degree) is an ultralight down sleeping bag that weighs 12 ounces (340g) and is insulated with 850-fill energy waterproof down. The Spark 1 has a sewn-thru building and a one-third-length zipper to save lots of weight. When stuffed the Spark 1 packs right down to the scale of a baseball (1.5L) making it good for journeys the place pack house is at a premium. Its unbelievably low weight will attraction to anybody making an attempt to shave ounces or grams from their pack weight.
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Specs at a Look
- Gender: Unisex
- Weight: 12 oz (Measurement common, Size 72″)
- Precise Weight: 12.5 oz on the SectionHiker digital scale
- Fill Weight: 6.3 oz
- Sizes: common,
- Sort: Mummy
- Packed Measurement: 1.5L
- EN Restrict Temperature Ranking: 40F (5C)
- EN Consolation Temperature Ranking: 48F (8.9C)
- Development: Sewn-thru
- Girth/Hips/Footbox (dimension common): 59″, 51″, 35″
- Insulation: 850 Fill Goose Waterproof Down RDS
- Zipper: One-third zipper, 2-way
- Zipper Facet: Left
- Draft Tube: No
- Shell/Liner Cloth: 10D Nylon RipStop with DWR / 7D Nylon RipStop
- Stuff Sack: Compression sack included and a material storage bag
- Go to Sea-to-Summit for full Specs
Ultralight Design Options
At simply 12 oz, how did Sea-to-Summit make this sleeping bag so light-weight?
First off, the sleeping bag is kind of tapered and is designed to fit your needs with out a whole lot of additional inner house. I can match into its 59″ shoulder girth (dimension common) however there isn’t an entire lot of additional room for me. The footbox is fairly spacious, nevertheless, and my ft can simply splay aside comfortably.
Subsequent, Sea-to-Summit makes use of very light-weight materials on the Spark 1 together with a silky 7D nylon liner and an ultralight 10D exterior nylon shell. Each of those materials are PFC-free.
Lastly, the Spark 1’s zipper is just one/3 size offering additional weight financial savings. As a result of it’s a warm-weather bag, it doesn’t have a zipper draft tube or a chest draft tube, which saves extra weight. The zipper is two-way and has a snap on the high so you’ll be able to unzip and vent the torso should you get too heat. The snap additionally takes any rigidity off the zipper, including to its longevity. Nevertheless, the zipper doesn’t have any anti-sag taping alongside its size, once more to save lots of weight, so it’s good to watch out to not have it jam or probably tear the liner and shell cloth when opening or closing it.
Insulation
The Spark 1 is insulated with 850 fill energy Nikwax “waterproof” goose down which is premium stuff by way of warmth-to-weight ratio. Larger fill energy down like this gives extra heat by weight than decrease fill energy down and is used to save lots of weight. The waterproofing makes the down dry sooner if it will get damp or moist
The down insulation is oriented in vertical baffles over the hips and chest and in horizontal baffles over the legs and ft to assist forestall down shift and maintain the down the place you need it. The baffle building is sewn-thru, fairly than being box-baffled to save lots of weight and maintain prices decrease. In sewn-thru building, the highest and backside cloth shells are sewn collectively to create tubes to carry the down in. Whereas this prevents downshift, it might create chilly spots on the seams.
Whereas the Spark 1 is rated for 40 levels, I’ve discovered it sleeps just a little chilly at 50 levels, even when used with an acceptable sleeping pad and lengthy underwear. It’s nonetheless a viable choice for hotter climate use, however I recommend you shakedown its consolation ranking earlier than relying on it near its consolation restrict.
Mummy Hood
The Spark 1’s mummy hood is fairly commonplace with a right-side elastic wire that permits you to cinch the hood closed. It doesn’t have house for a pillow, however it’s vast sufficient that you may comfortably roll over onto your facet whereas carrying it. The snap on the high of the facet zipper helps seal the hood on the left facet and keep its form even when the facet zipper is just not absolutely closed. The hood can also be fairly unobtrusive should you resolve you wish to unzip up the sleeping bag and use it extra like a quilt.
Advice
The Sea-to-Summit Spark 1 (40) is an ultralight sleeping bag that weighs 12 ounces and is optimized for backpacking journeys the place house and weight are at a premium. It’s by far one of many lightest sleeping luggage or backpacking quilts accessible at this time. For instance, a customized Enlightened Tools Revelation Quilt with comparable specs (fill energy, cloth weight) weighs 3 ounces extra. The benefit of utilizing a sleeping bag just like the Spark 1 over utilizing a backpacking quilt, in addition to the apparent low weight and packability, is that you just’ll have a draft-free expertise with no need a bivy sack as a result of it’s utterly enclosed. Should you favor a sleeping bag over a quilt and need an ultralight sleeping bag, the Spark 1 is a viable choice value contemplating.
Disclosure: Sea-to-Summit donated a sleeping bag for assessment.
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Final up to date: 2023-07-20 21:26:30
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