Name: Eric Lavering

Age: 18

Gender: Male

Height: 6’3” (1.9 m)

Weight: 200 lbs (90 kg)

Shoulder/Waist girth: 48” (122 cm)/ 33” (84 cm)

Email Address: lavering@montana.edu

Home: Bozeman, Montana

Date: April 26, 2005

Backpacking background: I started backpacking around eight years ago with various bible camps and church groups. I have recently started going out on my own trips with friends and family. I hike in the mountains of Western Montana. I have been lightening my load the last two years and am now down to a total pack weight of less than twenty pounds (9 kg) for a 4-5 day trip. I hope to continue lightening up as much as my budget will allow.

Manufacturer: Marmot

Year of manufacture: 2004

URL: www.marmot.com

Listed weight: 1 lb 8 oz (680 g)

Weight as delivered: 1 lb 9 oz (710 g)

MSRP: $329 USD

Materials: Pertex Quantum Ripstop (shell), Pertex Quantum Taffeta (lining)

Mummy shape

900 fill power goose down insulation

Length: fits to 6’6” (1.98 m)

Shoulder girth: 64” (163 cm)

Hip girth: 60” (152 cm)

Foot girth: 42” (107 cm)

The product was tested in the semi-arid mountains of Western Montana. Elevations were from 5000 - 8000 ft (1500-2400 m) with temperatures from the mid 50s F (around 13° C) down to around freezing. Weather included one night of hard rain and some light wind.

The Hydrogen sleeping bag is the lightest that Marmot makes, and is part of its 900 down series. The bag has a black Pertex Quantum ripstop outer shell fabric with a Quantum taffeta inner lining. The bag has 900 fill goose down insulation. I purchased this bag from REI at the beginning of summer, 2004. The MSRP for the long version of the bag was $329. The bag had to be shipped from another store, and it quickly arrived in a large cotton storage sack.

My first impression of the bag was that it looked like a large black garbage bag. The Pertex Quantum shell material has a slight shine to it which gives it this appearance. I soon got over the appearance of the Pertex and was next amazed at the texture of the material. The fabric is amazingly soft and smooth, and not at all plastic-like as it looks. The bag seems to be very fragile. Quality of workmanship on the bag appears very good, with straight stitching and no loose threads.

I couldn’t resist giving the bag a test run, so I jumped in and tried everything out during a night spent on the living room floor. The bag is surprisingly roomy compared to other bags I’ve used. I searched, but didn’t find any information on whether extra girth was added for the long version of the bag. The ½ length zipper could be a little longer, as it makes a little squirming necessary to get in and out of the bag. Just a few seconds of wiggling and this problem is solved, though. The zipper itself is small but functional and I have had no problems with material getting caught in it. The zipper can be used from inside or outside of the bag and has a zipper pull that is large enough to make the job simple. The length of the zipper is backed by a generously filled draft tube. The hood is well designed, having a good shape that snugly wraps around my head when cinched up. I find that the draw cord for the hood is a little hard to reach from inside the bag, but not any more so than other bags I‘ve slept in.

My first real test of the bag came when a few friends and I went on a weekend trip in the Bitterroot mountains in far western Montana. Friday night was spent at the trailhead. There was light rain at night and the temperature was mild. I slept well throughout the night. Saturday night, however, I slept in my Tarptent Squall with my friend, who is also fairly large. I had accidentally pitched the tent a little low, so we were both touching the walls of the tent at night. During the first half of the night it rained fairly heavily and the tent walls became very wet with condensation. Again, the temperature was mild. I was perfectly warm, and could have easily fallen asleep, but was worried about the down getting wet from condensation. I continuously checked the bag to see if the loft of the down was diminishing, but it stayed lofty and warm through the night. I was very pleased and surprised by the ability of the Pertex Quantum to keep water away from the down even when the fabric was soaked. In the morning I set the bag out on a rock in the sun and it dried out completely by the time we had taken down camp.

My next trip with the bag was a five day hike in Montana’s Anaconda-Pintler Wilderness. The weather was warm and dry, so I wasn’t able to really test the ability of the bag at extremes. I did, however, really begin to appreciate the comfort of the bag. I am in love with the Pertex Quantum on this bag, not only for its water repelling properties, but also because it just feels great. I never really had any complaints about the feel of the material on my other bags, but once I slept in the buttery smoothness of a Quantum bag, I never wanted to go back.

Next, I went on an eight day trip in the Spanish Peaks wilderness area near Bozeman, Montana. Temperatures during the trip hovered around in the 30s F (-1° - 4° C) for the whole week, giving me a good opportunity to test the comfort range of the bag. The bag performed well down to the advertised 30° F (-1° C), but I would not recommend relying on it in much colder conditions. I am generally a slightly cold sleeper when backpacking, and I only needed to wear regular clothing and a warm hat under the bag when sleeping in a tent. We slept in tents for all of the nights but one, when the stars were just too tempting and some of us slept out. That night we were camped at the highest elevation of my experience with the bag (around 8000 ft or 2400 m). There was some light wind during the night, and the temperature was right around freezing. I tried sleeping in the bag with just regular clothes and a warm hat again, but later had to get up and put on a lightweight fleece jacket and fleece mittens. Afterward I was comfortable and slept soundly through the night. One should note that we worked fairly hard on this trip, but also ate pretty well, so your results at these temperatures could be slightly different than mine.

-Light weight

-Quality materials and craftsmanship

-No-frills design

-Everything manufacturer claims it to be

-High price

-½ length zipper a little short (not a big deal at all)

-Hood draw cord a little hard to reach (also not a real problem)

At only 25 oz (710 g) and warm enough for all my summer trips, the Marmot Hydrogen is definitely a superb warm-weather bag. With the quality materials and workmanship, I know I’ll be using this bag for a long time. The only real downfall of this bag in my mind is the price. This is an expensive sleeping bag, but the excellent materials, quality construction and extremely light weight make it worth the price to me.