Full Length Locking YKK Two Way Zipper with Zip-Guard Slider
Down Defender to Improve Water-Resistance in Wet Conditions
Nautilus Multi-Baffle Hood
Internal Stash Pocket
Snagless Insulated Draft Tube
Hood Draw Cord
Two Way Zipper Sliders
Zipper Garage
Stretch Tricot Baffles
Two Hang Loops
Stuff and Storage Sack Included
Description
The Hydrogen 30° Sleeping Bag delivers enough warmth for cool-weather adventures and backcountry excursions, yet still keeps base weight at a minimum on light and fast climbs. Featuring Pertex® Microlight on the exterior, its lofty 800-fill-power-down insulation and water-resistant Down Defender treatment will keep you warm and dry. After an epic day on the mountain, give your feet a rest in the roomy wrap-around footbox. Smooth, curved baffles help keep the fill in place, while the nautilus multi-baffle hood with a drawcord, snagless insulated draft tube, and full-length two-way zipper with a zip-guard slider limit heat loss. If the interior gets too warm, use the fold-down secondary zipper to get some air. Tuck small items into the internal stash pocket.
Specifications
Bag Temperature Fahrenheit:30°F
Bag Temperature Celcius:-1°C
Tested Comfort:33.6°F / 0.9°C
Product Weight:1lbs 7.3oz (665g)
Main Fabric:Pertex 20d 100% Nylon R/S 1.03oz/yd
Lining Fabric:30d 100% Nylon DWR 1.09 oz/yd
Insulation Type:Down
Insulation Material:800+ Fill Power Goose Down
Zipper Location:LZ
Shoulder Girth:61in (157.48cm)
Hip Girth:56in (142cm)
Footbox Size:39in (113cm)
Includes Stuff Sack:Yes
Stuff Sack Size:6 x 12 in, 15.2 x 30.5 cm
Includes Storage Sack:No
Includes Compression Stuff Sack:No
Compressed Volume:280ci » 4.6 liters
Stash Pocket:No
Style Number:24120
Rated 3 out of
5 by
Radu from
It's kinda expensive for what deliversI can't say I don't like it, but I expected more based on the specs and at this price. Maybe it's just me, maybe I'm a very cold sleeper, but at +5C i'm not that good if I don't have two layers of sleeping pants (1 merino wool and one fleece) and at least 2 layers on my body (syntehic base layer + a 320g fleece). At 0C, very close to what they say is the rating of the bag, I need a down jacket over those layers. I'm male, age 38, I have 1.80m and 72kg. Another thing: based on my scale, wich has no problem at all (it was tested), it dosen't have 665g, it has 733g. Almost all companies give you the wrong weight, which is dissapointing.
Date published: 2019-04-09
Rated 5 out of
5 by
Spider from
Warmer Than a Typical 30 BagThis is more like an Uber light 20 bag. At 18F there were only a couple places where my legs were deflating the loft that I felt some cold. But multiple nights below 25 proved this bag for me. First night out was sub 30 and I ended up taking off my puffy cause I was getting hot. It does handle damp well too as I swamped my foot box on a couple occasions on condensation. Yet it kept its loft and warmth.
As a thru hiker, I need a bag thats light and versatile for ever changing climates. This is the bag. It works awesome as a quilt too because of the double zippers. I couldn’t be more satisfied. I’m going to get the helium 0 bag for winter now. Hope it’s as wonderful as the H2.
Date published: 2020-12-18
Rated 2 out of
5 by
Marmot96 from
Seam pulled out on first nightThe very first night I used this, the seam pulled out on the 8th baffle from the top. Luckily I was able to return it as I was very gentle and didn't lose too much of the down filling.
I did spend 4 nights in the bag since I was on a backpacking trip, and it kept me warm until about 28 degrees at which I needed to add a lightweight jacket. The footbox could use a little more down as my feet were a little chilly even when I was warm.
Date published: 2017-08-21
Rated 5 out of
5 by
Coyote Kate from
Best Northwest Bag!This particular purchase was a gift for my son but I have owned this same bag for 5 years and I love it. It's extremely light weight for back packing (and stuffing in a kayak), very warm, and durable. I use the bag from spring to fall in the Pacific Northwest and Canada. My boyfriend has the same bag and its 15 years old and still being used. If you are looking for a high quality light weight bag this is it.
Date published: 2017-01-11
Rated 5 out of
5 by
Flatfoot from
WarmI bought this sleeping bag for my recent trip to Glacier National Park. We backpacked 3 nights backcountry. August, Temperatures dropped into the high 40's low 50's range in the valleys. Definitely cool in the morning. I slept under the stars, no tent, and just this sleeping bag and a lightweight tarp for precaution if it rained. I wore shorts, wool socks, and long sleeve mid layer. I was warm all night. Like how it wraps over your head!
Date published: 2017-08-16
Rated 5 out of
5 by
Skye from
Perfect for UL BackpackingI did a ton of research on UL bags for backpacking before making this purchase, and I am so happy with this bag! It is really light and packs down tiny, almost to the size of a Nalgene bottle. Kept me warm on two alpine lakes backpacking trips, one at over 6,000 feet. I do tend to sleep cold, but this has been perfect for summer. Also, love the color, but it's more olive than the images show, not super yellow at all. My only complaint is that I wish it was a little wider/roomier, but still is really comfortable for me (I'm 5'5", 112lbs and a side sleeper). For larger people, it may feel a bit tight in the shoulders/width.
Date published: 2021-08-06
Rated 5 out of
5 by
Coldfinger from
Nice upgrade of a great bagThis is my second Hydrogen sleeping bag and it’s a nice upgrade. A bit warmer and a bit lighter. I need a bit more warmth in an ultralight sleeping bag as I live in Wyoming and this bag delivers! DWR treated down performs so well in cold and/or damp conditions. There are lighter bags out there but for a LOT more $$.
Date published: 2019-11-06
Rated 5 out of
5 by
MichaelH from
Great summer backpacking bag and good bang:$After perhaps 5 years of procrastinating a much-needed bag replacement, I picked up this Marmot Helium this winter. I deliberated on some other Marmot, Mtn Hdwr, Western Mountaineering, and other name-brand bags and ultimately chose the Hydrogen is a really good balance of price/performance.
Primary uses are/will be summer-fall backpacking in the inland Northwest, primarily north-central Washington state, where it's pretty dry/continental weather patterns. I'm not interested in trying to facilitate winter camping (I have an old Marmot 0F bag for that anyways). My primary criteria were good construction, well sub-2lb, highly packable, and warm enough for high elevation summer backpacking.
After 1 weeklong trip primarily in Escalante, I'm very happy with the bag. It packs down smaller than my old REI sub-kilo but is warmer. It seems well constructed, not a hint of escaping down. I didn't pay attention to the materials but the interior is less clammy feeling than my old REI down bag. The zipper is smooth and not under-built. Really comfy hood and adequate footbox.
I'm 6' and 200lbs and I am at the upper limit of sizing for this bag. It's snug but comfortable but if I was 6'1" or any fatter, I'd have gone for the long. I was warm on my April trip at 6-8,000ft in Utah with temps falling down to the upper 20's at night (on a high R-value pad), wearing boxers and a t-shirt.
Final word: there are probably nicer bags out there but this is still an excellent bag for the money; a great balance of price:performance. I'd definitely purchase it again and recommend it to someone who wants a high performance backpacking bag but doesn't want to spend $450 for it.
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Backed by Marmot's Lifetime Warranty