Sometimes pack real estate margins don’t have room to budge. Like when sea kayaking or bikepacking—space is limited. Listening to the market, Australian brand Sea to Summit released its Spark series in 2013, with the Spark Sp I (46?), Sp II (35?), and Sp III (25?).
This suite of bags was designed for those going exceptionally light without skimping on warmth. The result is one of the best warmth-to-weight ratios on the market for a hooded sleeping bag.
We tested the Spark SpII this spring on a bike-rafting trip across the Owhyee desert of Southern Idaho. Here is our first look at this super-minimal but still effective sleeping bag.
The Gear: Sea 2 Summit Spark SpII Sleeping Bag (35 degree rating)
Where To Test It: Bike-packing, sea kayaking, ultralight backpacking.
Who’s It For: 3-season minimalists.
First Impressions: The white bag compressed to a ghostly size that nearly vanished in our bike bags. But it blossomed like a desert flower when we unfurled it in the tent.
To get it down to its welterweight, Sea to Summit cut all the trimmings. There’s no draft collar, it’s got a ? length zipper, and it’s tailored with a svelte cut. It’s not a straightjacket, but at 165lbs, I had to wiggle in and out of the bag each night. The shorter zipper also meant there wasn’t an efficient way to vent heat other than to strip layers.
This makes the SpII best for surgical strikes, where your mission is in and out during a specific temperature range. If you are looking for a quality hooded bag that saves weight while buying back some pack real estate, this could be your weapon of choice.
Boring But Important: Materials: 10D Pertex Quantum shell, 15D nylon liner; 1/3 length YKK 3 left-side zip; 850+ ULTRA–DRYDown fill. Total weight: 16 oz (regular size), 18oz (size large).
Important Specs: The Spark SpII mixes sewn-through lateral baffles over the legs with continuous baffles over the torso. Furthermore, the SpII varies its fill 55/45 over the torso/legs. Together, this differential fill lofts the potential space for heat where you need it most: over your core. The hood has a simple drawcord on the right, snugging around the face. The ? length zipper runs down the left, giving you a little extra room to get in and out of the bag.
Made In: Designed in Australia; made in China
Killer! At 16oz, the SpII compresses smaller than most down jackets! The differential fill along with the combination of sewn-through and boxed baffling is a weight cutting design that maximizes warmth. Its slim cut reduces the amount of empty space requiring the body to heat. And the 850+ DRYDown fill is the down feather in this exceptionally efficient bag’s cap.
Flaw: The 3L compression sack packs down small. But it’s also small to start with. It takes a bit of effort to stuff the sleeping bag into the stuff sack, which is harder to do when cold and clumsy in the morning. The hood is fairly minimal, and with the lack of a draft collar, it makes the SpII prone to spilling heat.
Who Should Buy It: Skinny three-season ultralighters who find themselves weighing an extra dinner over extra insulation.
Contact Brand/More Beta: Spark SpII
—Steve Graepel is a contributor. Our “First Look” column highlights new gear arrivals at GearJunkie.com. Photos © Monopoint Media LLC