A warmer spark for minimalist missions in colder conditions. The SpII has the same streamlined design, with additional proportional fill to concentrate warmth where it’s needed most.
Using the warmth of 850+ loft 90/10 Premium goose down, the amazing moisture protection of Ultra-Dry Down, and a micro-weight 10D Nylon shell and 15D lining, Sea to Summit have created one of the best warmth for weight minimalist sleeping bags available. The Spark is an ultra light bag with many possible uses. Its balance of size, weight and warmth make it an excellent summer sleeping bag, especially for weight and space conscious cycle tourers and ultra light walkers. It also works well as a liner bag, slipping inside another sleeping bag to add one or two seasons to its rating. The Spark compresses so small, Sea to Summit had to re-engineer the compression-sacks to make one that reduced sufficiently. The Ultra-Dry Down protection makes the Spark an impressive hard-alpine or adventure racing sleeping bag, where down has never before been a viable option, and weight is simply not tolerated.
Adapted mummy cut
10D Pertex quantum case for minimum weight and volume
Stitched, circular rooms on the legs
Quilted Chambers in box form on the upper body
55/45 fill balance
Uneven filling to concentrate heat to the centre of the body
Custom hood with drawstring cord
Cone-shaped foot box
1/3 length YKK #3 side zipper
Includes light 15D Ultra-sil compression bag, mesh Storage cell and laundry bag
For travel, adventure racing, cycling, liner bag, ultralight hiking and alpine climbing
Compression volume: 2.9 L
Down: Ultra-dry down 850 + loft, European goose down
OK, quality comes at a price, but even so this is an expensive bit of kit and in terms of value for money I give it a 4* rating. I appreciate it is 95% goose down, from managed sources and carries all the certification to prove it. There is no doubt it is one of the lightest sleeping bags and compresses down very small. It is a struggle to get it into its stuff sack, but once done, it is a cylinder of only about 10" long x 4" diameter. Furthermore, as soon as it is taken out of its stuff sack, it very quickly lofts. It is very light and the material is very comfortable next to the skin, although that said, I needed socks, long-johns, long sleeved top, down gilet and skull cap to try and keep warm! More about this later.
SIZE: I'm 6' and not a large bloke. I am about 80Kg and yet I found there was not a lot of room in this bag. You could put your arms down, or folded over your chest/abdomen, but there was very little ability to adopt a more (for me) comfortable sleep position. I cannot imagine how a big bloke would get on with this, particularly if broad shouldered. It was long enough, but simply not wide enough to be comfortable when trying to lie on your side. 4* again as a result.
When trying to move within the bag, because the bag is a snug fit on the torso and shoulders, instead of freely moving your body within the bag, the bag moved with you, thereby resulting in the less insulated bottom of the bag ending up over your backside or shoulders/torso. This meant that the full insulating properties of the bag did not cover all of your body parts. You soon find out the difference in insulating properties between the upper and lateral sections (more insulation) and the lower section (less insulation). You get cold.
The zip is only 3/4 - not a problem for me on my trip (which was unexpectedly cold), but could be an issue when the nights are unusually warm and you just want to drape an open bag over you. You can't with this one. 4* again, but I appreciate this would have made the bag slightly heavier to have a full-length zip.
The extra shape to accommodate the feet is good, but I would expect this to be a standard feature in any bag these days.
WARMTH: Read the spec carefully - there are 3 variations to this model. I got the Spark II and thought this would be ok, but on a recent mid-May) back-packing trip along the Hadrian's Wall path I encountered high pressure all the way, with little or no cloud cover - hot days and unusually cold nights. The temperature went down to 2 degrees C on some nights and not much warmer on others. The Spark II is "comfort zone 7 degrees" - ordinarily this should have been OK for the trip, but it wasn't. I regretted not taking my much cheaper, but heavier bag rated to 2 degrees comfort zone and I also regretted not looking at the weather forecast in more detail, but its all experience. So at 2, 3, 4, 5 degrees C, even with thick socks, pants, long-johns, long-sleeved top, down gilet and skull cap, I was cold - I mean REALLY cold. I even put on my walking trousers and walking top, which caused more restriction, more discomfort, sleeplessness and still not enough warmth.
Light gear comes with some drawbacks. My base camp pack weight (minus food and water) was about 16lb. For an additional couple of pounds, I could have been warmer at night and so I would advise anyone thinking of buying this bag to consider carefully what they need it for. I would reserve this for summer and early autumn, but definitely not spring or later autumn. I WOULD use this in Winter, but only to use as a liner for my larger other bag. The smaller Spark II will fit well inside my other bag and together I would be warm even in winter, combined with a good insulating mat and a 4-season tent.
On a smaller hike, I was able to collect first impressions.
For me (175 cm) the sleeping bag is well cut and I do not feel constricted. Since I use an inlet in the sleeping bag, nothing can say about whether the sleeping bag material feels pleasant on the skin. But with the pure touch it does not feel cold or unpleasant.
Definitely keeps the sleeping bag pleasantly warm. Although I could not test the extreme range yet and I belong to the group of people who are not frozen.
Very great, the sleeping bag can be super small compress. Despite the incredibly light weight, the Pertex material makes a robust impression.
For a tour in the summer the Spark SP II is too warm. Since it only has a 1/3 zipper, you can not use it as a blanket. This is the only criticism - a continuous zipper would have increased the weight, but also the range of application.
But for hiking in the mountains, Scandinavia and in the spring / autumn a genial sleeping bag.
A clear purchase recommendation when it comes to weight and pack volume.
Auf einer kleineren Wanderung konnte ich erste Eindrücke sammeln.
Für mich (175 cm) ist der Schlafsack gut geschnitten und ich fühle mich nicht eingeengt. Da ich zusätzlich im Schlafsack noch ein Inlet nutze, kann nichts darüber sagen, ob sich das Schlafsackinnenmaterial angenehm auf der Haut anfühlt. Doch beim reinen anfassen wirkt es weder kalt noch unangenehm.
Definitiv hält der Schlafsack angenehm warm. Wobei ich den Extrembereich noch nicht testen konnte und ich zu dem zu der Gruppe von Menschen gehöre, die nicht verfroren sind.
Ganz toll, der Schlafsack lässt sich super klein komprimieren. Trotz des unglaublich leichtem Gewichts macht das Pertex Material einen robusten Eindruck.
Für eine Tour im Sommer ist der Spark SP II zu warm. Da er nur über einen 1/3 Reißverschluss verfügt kann man ihn nicht wie Decke benutzen. Das ist der einzige Kritikpunkt – ein durchgehender Reißverschluss hätte zwar das Gewicht erhöht, dadurch jedoch auch das Einsatzspektrum.
Doch für Wanderungen in den Bergen, Skandinavien und im Frühjahr/Herbst ein genialer Schlafsack.
Ein klare Kaufempfehlung, wenn es um Gewicht und Packvolumen geht.