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 development 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 enchantment 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 Score: 40F (5C)
- EN Consolation Temperature Score: 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 Material: 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 sort of tapered and is designed to suit you with out quite a lot of further inner house. I can match into its 59″ shoulder girth (dimension common) however there isn’t a complete lot of additional room for me. The footbox is slightly spacious, nonetheless, 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 only one/3 size offering further 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 prime so you’ll be able to unzip and vent the torso when you get too heat. The snap additionally takes any pressure off the zipper, including to its longevity. Nonetheless, the zipper doesn’t have any anti-sag taping alongside its size, once more to save lots of weight, so you could watch out to not have it jam or probably tear the liner and shell material when opening or closing it.
Insulation
The Spark 1 is insulated with 850 fill energy Nikwax “waterproof” goose down which is premium stuff when it comes to warmth-to-weight ratio. Increased fill energy down like this supplies 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 stop down shift and preserve the down the place you need it. The baffle development is sewn-thru, slightly than being box-baffled to save lots of weight and preserve prices decrease. In sewn-thru development, the highest and backside material shells are sewn collectively to create tubes to carry the down in. Whereas this prevents downshift, it may possibly create chilly spots on the seams.
Whereas the Spark 1 is rated for 40 levels, I’ve discovered it sleeps somewhat chilly at 50 levels, even when used with an acceptable sleeping pad and lengthy underwear. It’s nonetheless a viable possibility for hotter climate use, however I counsel you shakedown its consolation ranking earlier than relying on it near its consolation restrict.
Mummy Hood
The Spark 1’s mummy hood is fairly normal with a right-side elastic wire that allows you to cinch the hood closed. It doesn’t have house for a pillow, however it’s huge sufficient you could comfortably roll over onto your facet whereas sporting it. The snap on the prime of the facet zipper helps seal the hood on the left facet and keep its form even when the facet zipper isn’t totally closed. The hood can also be fairly unobtrusive when you resolve you wish to unzip up the sleeping bag and use it extra like a quilt.
Suggestion
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 baggage or backpacking quilts out there in the present day. For instance, a customized Enlightened Tools Revelation Quilt with comparable specs (fill energy, material 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 simply’ll have a draft-free expertise while not having a bivy sack as a result of it’s fully enclosed. For those who favor a sleeping bag over a quilt and need an ultralight sleeping bag, the Spark 1 is a viable possibility price contemplating.
Disclosure: Sea-to-Summit donated a sleeping bag for evaluate.
Examine 1 Costs
Final up to date: 2023-07-20 21:26:30
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