Mountain Equipment Helium 400 Sleeping Bag | Review - Outdoors Magic

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Mountain Equipment Helium 400 Sleeping Bag | Review

Mountain Equipment's redesigned three-season lightweight is a great mix of warmth, weight and cunning design.

‘Mountain Equipment Helium 400

Outdoors Magic: Good blend of warmth, weight and value, hood design with magnetic catch, box-wall construction throughout, decent foot-box and overall fit, smooth, well-baffled zip. Neat waterproof stuffsac.

Outdoors Tragic: Slimmish alpine fit won’t suit everyone, misplaced duck down snobbery.

Outdoors Grabbit? ME’s redesigned sleeping bag range for 2017 is lighter, more efficient and has some great detail touches like a magnetic neck head-opening fastener, differential drawcords and an excellent, well-baffled classic side-zip configuration. Sure, it’s duck rather than goose down, but it works fine and there’s intrusive mal-odour of mallard. The upside is that it’s good value for a hard-to-fault, decently packable, good performing three-season all-round sleeping bag.  A good choice.

Full Specification

Two to three-season lightweight sleeping bag / 385g Down Codex, traceable 700+ fill power duck down / HELIUM 20 outer and Supersoft 30 inner fabrics / box-wall construction throughout / mid-level side seams / five-baffle anatomically shaped hood / four-baffle anatomically-shaped and offset foot-box / full length Gemini™ zip baffle /

Ratings Comfort 3˚C – Limit of Comfort -3˚C – Extreme -19˚C

Full Review Below

There's plenty of down in the well-fitting, easy-to-adjust hood complete with neck baffle - image: Jon
Flat and round cord profiles make it easy to adjust the hood first time in the dark - image: Jon
The magnetic catch for the top side fastener is genius and pretty much closes itself while staying easy to open - image: Jon

Mountain Equipment Helium 400 | Performance

This spring Mountain Equipment has completely redesigned its sleeping bag range with a lot of input from down guru Matt Fuller, aka ‘Doctor Down’. You can get more detail in our recent detailed look at the new range, but in brief, the whole range has become simultaneously lighter and warmer.

That’s due to scientific analysis of how much and what density of down to use in different areas of the bag, an improved zip design with a more efficient baffle and the careful use of optimised lightweight fabrics.

The brand’s also brought in some really neat detail features like a cunning magnetic neck opening fastener, that pretty much closes itself, drawcords that you can differentiate between in the dark thanks to different shaped cord and a simple but effective waterproof stuff-sac with a basic air-expulsion valve.

Roll-top waterproof stuff-sac uses a neat, eyeleted ‘valve’ to help expel air and give that sought after vacuum-packed effect – image: Jon

In use, we’ve found the Helium 400 hard to fault. It’s not the lightest design in the ME range – check out the new Firefly if you want ultimate lightweight warmth – but it’s a good balance between warmth, pack size and decent value and really well engineered and designed.

The fill, housed in slanted, box-wall baffles for maximum efficiency and no cold spots, is actually duck rather than goose down, but there’s no tell-tale mallard odour and performance is decent. Goose down, by the way, has become increasingly scarce and expensive, apparently because the Chinese have discovered duvets. Who knew?

Anyway, the bag’s proved a seamlessly effective spring companion. The fit is ME’s ‘alpine’, which is quite slim and athletic, so worth trying if you’re more heavily built and all the new features work as advertised. No issues with the well-shaped, warm foot-box even when we accidentally slept with it pressing on the foot of the inner tent, doh…

No faulting the components. Proven HELIUM 20 fabric is light but completely windproof. Zip gets redesigned ‘ Gemini baffle – image: Jon

The hood’s reassuringly lofted and warm, the magnetic catch is genius. It pretty much shuts itself when the two components get close, stays secure in use, but is easy to open when pulled in the correct orientation.

We also like the differentiated cords for the hood opening. The front one is flat, the back, rounded. That means you can tweak the hood fit in the dark using feel to tell the difference between the cords. It’s a small touch, but a nice one.

W had no issues or cold spots from the full-length, non-snagging side-zip, You can open it from the bottom for venting or just unzip from the top for ease of movement, reading and/or cooking from your bag and so on.

Finally, even the simple, roll-rop, waterproof stuff-sac has been carefully thought out. A simple eyeleted air valve makes it super easy to squeeze out excess air before you cinch it all up and stash it away in your pack. And when you get home, a cunning cube-shaped storage sack makes it easier to pack away under your bed.


Plenty of loft and the soft liner fabric is comfortable and quiet in use - image: Jon

Mountain Equipment Helium 400 | Verdict

We chose to review the Helium 400 from th new ME range because we figured it was a bag that made sense for a lot of UK users – if you want warmer there are also 600 and 800 versions or you could go for broke and invest in something higher spec – meet our new sleeping bag crush

We reckon we were about right too. If you sleep reasonably warm, you could probably get away with this bag into early and late winter and certainly for the rest of the year. It’s decently warm, impressively packable and reasonably priced.

What makes it stand out though, is the overall attention to detail and sleek efficient fit, though that’s also a downside for some. In short, a cracking all-round, go to sleeping bag that does a good job of show-casing ME’s revamped range.

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