Light on the back, warm in the sack.
Being a member of Marmot's Ultralight series of sleeping bags, the Hydrogen 30-Degree Down Bag is a great option for the ounce-counting backpacker that still appreciates a good night's sleep after a long day on the trail. To keep the Hydrogen warm in the face of condensation, Marmot used Pertex Microlight fabric to save weight, increase breathability, and protect the down insulation from light moisture. Better yet, the insulation consists of 800-fill down that's been finished with Marmot's Down Defender treatment to help prevent it from clumping and ultimately losing insulating properties should it happen to get wet. The basic mummy shape efficiently traps warm air and has an anatomic footbox to give your feet some extra room to roam once you're in for the night, and comes with either a left- or right-handed full-length zipper to please right- and left-sided sleepers. An additional zipper on the opposite side allows the front of the bag to fold down for added comfort when you're sitting up in your bag waiting for a storm to pass.
- 30-degree temperature rating
- 800-fill down insulation
- Down Defender water-resistant treatment
- Mummy shape with anatomic footbox
- Pertex Microlight 20D nylon ripstop
- Second fold-down zipper
- Stuff sack included
- Item #MAR00T4
What do you think about this product?
December 17, 2019
Warm and Compactable Bag
This bag is a warm, durable, and compactable 3-season bag. I've spent some pretty chilly shoulder season nights in it and it kept me warm, but its best as a summer bag ... especially in the alpine.
March 27, 2019
The bag packs lots of warmth for how light it is and the interior pocket is so convenient to stash your phone or batteries to keep warm through the night. The zippers are fantastic as well - very easy to zip and unzip.
October 25, 2018
Great bag, used it while hunting and camping on a ridge this winter, the bag kept me warm enough to have to unzip a little despite heavy winds and snow on the tent. Light enough to pack in and compresses to a small size. take 20% off coupons from coupon-code.info
September 25, 2018
Good backpacking bag
Decently light, very compact-able and easy to store. Isn't super warm for cold nights up in the mountains, but fabric is very comfy and easy to sleep in.
June 16, 2018
I think I know why people complain about being cold in bags with a high down fill. This 800 fill bag has 5-inch baffles which allow for the down to easily clump and shift. When I first took a look at the bag and held it up to some light I could see dead spots in the baffles. I spent a good 10 minutes manually lofting the bag and checking to see that the down had shifted to the right place. This would be a royal pain to manage when I'm out on multi-day treks or mountaineering. Let's just say when I am working hard in the wild, I do not want to fuss with my gear. I would recommend that designers consider dropping baffle sizes down to 3" or 4" depending on the fill to prevent the down from wandering around. Overall this bag felt very durable for being so lightweight, but I think there are better options out there.
November 26, 2017
Awesome Summer Bag!
This is my go to sleeping bag for summer backpacking. With a temperature rating of 30 it keeps you warm through unexpected summer snow squalls, but isn't too hot for most nights (I just use it as a blanket on warm nights). At only 1 lb 7.5 oz it's one of the lighter bags on the market, at a fraction of the price of some of the other bags in it's class. As with all Marmot products, this bag is extremely well made, and is holding up great after more than 4 years of heavy use. Overall, I am extremely satisfied with this sleeping bag and would highly recommend to all!
November 8, 2017
Great lightweight bag
This is my go to bag for most of the year. Great combination of ultralight and warm. Compressible, comfortable, nice smooth fabric. Regular size is good for my 6' height. I sleep pretty warm, so usually in just a t shirt. When temps drop below 35-40, I'll pull a jacket in, over my shoulders. My bag is about 7 years old and lacks a draft collar, but the void can be filled with an extra shirt or the jacket when cold. I value the double zipper to open foot box in warmer weather- many ultralight bags lack this. I've slept at 30 degrees a number of times and think the rating is about right. In colder weather, I pack my 15 degree Marmot Pinnacle.
November 9, 2017
Great review, thanks Keith!!
September 24, 2017
Not as warm as expected
Finally got a chance to try this bag out this past weekend. The bag is rated 30 degree. Nights were around 30-32, maybe a little less. From all the reviews I read I thought I would be fine. I was really cold, even with double long johns and my down sweater. I would return it if it weren't already past the 30 day limit.
Daniel O Soreonson
November 1, 2017
Daniel, Are you usually a cold sleeper, or did you go to bed cold? I've used a 20 degree bag in 45 degrees but stayed cold all night because I went to bed cold. What is your build and size purchased? Also, perhaps your double long johns and down sweater were inhibiting the insulation's ability to retain heat (compressing the down). 12 ounces of 800FP down should be plenty of insulation for those temperatures, in my own experience.
October 4, 2018
Daniel, A 30 degree bag does not mean you will be comfortable down to 30 degrees. It means you will survive. I highly recommend Marmot sleeping bags.
September 24, 2017
I have both a Hydrogen and a Helium bag, and I love them both. These bags are both incredibly warm and light. This bag is so light that I barely even notice it on very long hikes and steep technical climbs, and it comes with a large storage bag to keep it loose for storage and a separate small bag for compressing it and taking it on hikes/climbs. The sleeping bag compresses so well that with almost no effort I can stuff it in the tiny sack and quickly be on my way. I tend to use the 30deg bag for high-altitude summer climbs, where the light weight enables me to climb hard and move quickly but it still provides good warmth in the cold nights. Once september comes or if there is a chance of any cold high-altitude weather I will take the 15deg bag instead, but for most mountain activities I have found the 30deg bag to be sufficient and worth the lighter weight, especially with an insulative pad and my layers on. I can't imagine a better bag and highly recommend it for alpine climbing activities in moderate weather, I only wish it were also available with left/right zipper options. I am 6ft tall and the regular works great with a little room for stuffing a few clothes at the bottom if necessary.
May 22, 2017
Its soft and easy to carry
I select this sleeping bag for its weight and small size compare to others in same temperature range, I took it out for an one night camping on top of a mountain of 1800m in summer. It is warm in most places but i feel cold spot at middle area, its somewhere around my belly. The room inside sleeping bag is big and its quite easy to move around. (i am a girl). Overall i will recommend this sleeping bag specially u want to reduce weight of your bag and dont want sacrifice too much on comfort
January 6, 2017
Nice and Warm
This is my first down sleeping bag, and first high end bag. I have used it once in the backyard with my son. The temperature range was from mid 40s to about 33. I slept in short socks a T-shirt and shorts. I found the bag to be quite warm at those temperature ranges. When I had the bag completely zipped I was too hot and a touch sweaty. With a partial zip down I was plenty comfortable all night, while my nose was a little chilly. I really like this bag and look forward to getting to use it at some lower temperatures to see how low the temps can go and me still be comfortable. I would say the temperature rating is spot on for my tastes. I would recommend this bag, after future uses I will come back and update.
August 22, 2016
I love this bag. In true Marmot fashion it is top quality, super light and packs small. There isn't a thing I don't like about this bag. I plan on using until the temps really dip here in Mich and then I'll pull out another of my Marmot bags. Highly recommend this bag.
July 3, 2016
Performance vs. weight beast
I bought this sleeping bag about three years ago because it was on sale and seemed light enough for our 5 day backcountry fly fishing trip we take twice a year. Took it to Clingman's Dome in February and was surprised when we got hit by weather totally out of the forecast. I was sure I was going to be very cold. Bag did great and also has enough girth for a side sleeper. Best gear I have, it has performed in every situation. Getting ready to buy a Marmot 0 degree bag this weekend. I highly recommend this bag, especially the performance, weight and packability. I think it is the best value in the market.
March 31, 2016
Warm and Light
I would very much keep this sleeping bag but i ended up returning it to buy a cheaper marmot sleeping bag. Although it's cheaper and not as warm as this one, I just can't afford something like this right now. Maybe one day in the future~
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