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Outdoor Research Helium II Review

One of the lightest and most packable in our review, with excellent mobility, good storm worthiness, and a sweet hood
outdoor research helium ii rain jacket review
Outdoor Research Helium II
Credit: Outdoor Research
Price:  $159 List
Manufacturer:   Outdoor Research
By Ian Nicholson ⋅ Review Editor  ⋅  May 14, 2019
  • Water Resistance - 30% 6.0
  • Breathability & Venting - 25% 5.0
  • Comfort & Mobility - 20% 7.0
  • Weight - 15% 10.0
  • Durability - 5% 5.0
  • Packed Size - 5% 10.0

Our Verdict

The Outdoor Research Helium II is essentially a cross between a super light rain jacket and a wind shirt; it offers the extended water-resistance of a rain jacket with the weight and packability of a wind jacket. This model is one of the most compact we tested, and it conveniently stows into a special built-in stuff pocket located on the waist of the jacket. It might lack the durability or the ventilation options to make it as versatile as other options in our review, but for backpackers, hikers, climbers, and trail runners who might leave their jacket in their pack 95% of the time, the Helium II is a perfect option.
Perfect stuff pocket
Super light
Good mobility
Above average weather resistance
No hand pockets
Loose wrist cuffs
No particularly durable
This contender is one of the lightest and most packable models we tested, making it ideal for moving light and fast, or to carry around as a just-in-case layer for protection against unsettled weather.

Our Analysis and Test Results

An extremely lightweight and exceptionally compressible shell, the OR Helium II is ideal for those looking to pack a rain protection layer that takes up as little weight and space as possible. Two reflective patches make this a great jacket for cool weather running and biking or as your only additional layer for longer trail runs.

Performance Comparison

outdoor research helium ii rain jacket review - the helium ii is super light and very compact, making it an...
The Helium II is super light and very compact, making it an excellent jacket to carry along on multi-pitch rock climbs. Brandon Lampley getting ready for the afternoon showers at Lumpy Ridge near Rocky Mountain National Park.
Credit: Amanda Fenn

Water Resistance

This jacket kept us dry, and the hood design was one of the best in the review. Like the Best Buy award-winning Patagonia Torrentshell, the elastic cinches extend up to the temple and not across the brow. The unique part of the Helium's design is that there are no cord locks at the side of the hood. A third elastic cord that tightens on the back of the hood also cinches the two on the side of the face. With the large, stiffened brim, these features work perfectly together.

The DWR treatment applied to the Pertex Shield+ fabric held up pretty well during our field and side-by-side testing. The one shortcoming with the Helium II's storm worthiness is the wrist/cuff design. Because this jacket only offers elastic on the wrist side and no means to tighten it, water can run down your forearms when reaching overhead into rainy weather.

outdoor research helium ii rain jacket review - despite its exceptionally low weight, the helium ii performed very...
Despite its exceptionally low weight, the Helium II performed very well in our real-world and side-by-side testing, though we do think its DWR treatment tends to wear out slightly faster than average and needs to be treated more frequently.
Credit: Ian Nicholson

As a whole, we were impressed by the storm protection this 6.5-ounce jacket provided; however, it wasn't nearly as storm worthy as several other jackets in our review, nor would it be our first choice for a weeklong trip with a high chance of precipitation every day.

Breathability & Ventilation

This jacket does not have any ventilation features, save the loose-fitting wrist cuffs (if you can call that a ventilation feature), which fit our lead tester's wrists with some room to spare, and thus let some moisture escape.

What this jacket does boast is respectable breathability; this fabric is more breathable than some coated options like DryVent (The North Face Venture 2) or H2No (Patagonia Torrentshell). The Pertex Shield+ fabric was breathable enough to keep us comfortable when generating some heat and sweat, as long as the temperatures outside were low, or we weren't working too hard and were wearing minimal clothes underneath.

outdoor research helium ii rain jacket review - this model is a perfect wind/rain jacket hybrid. it moves...
This model is a perfect wind/rain jacket hybrid. It moves exceptionally well and weighs next to nothing.
Credit: Amanda Fenn

The Helium II is breathable enough for cooler or drizzly early morning runs. However, because of the lack of venting options, if you're a sweaty person or looking for something more than super-light rain protection that lives at the bottom of your pack, you'll want to consider other options in our fleet.

outdoor research helium ii rain jacket review - the helium ii offers some of the best range of motion of any jacket...
The Helium II offers some of the best range of motion of any jacket in our review. The only jacket scoring better was the (much more expensive) Arc'teryx Zeta SL.
Credit: Ian Nicholson

Comfort & Mobility

Despite a truly minimalist design, the Helium II doesn't give much up for its range of motion or overall mobility and was just above average overall. For "comfort" in the traditional sense, it's a little lacking compared to most of the jackets in this review, as it doesn't feature small nods to comfort, like a micro-fleece chin patch.

outdoor research helium ii rain jacket review - despite being the lightest shell in our review, the helium ii...
Despite being the lightest shell in our review, the Helium II managed to also feature one of the better hood designs. It cinched down nicely, kept our head dry, and still kept an above average amount of peripheral vision when we turned our heads.
Credit: Ian Nicholson

Hood Design

This jacket does deliver an excellent, well-designed, easy to adjust hood that fits over a bike or climbing helmet. It has a unique elastic cinch system that our testers loved, and the hood is comfortable when worn with a ball cap or a rock climbing helmet. The zipper pulls on the waterproof main zipper and chest pocket have some of the easiest to grasp pulls, which are excellent for gloves.

outdoor research helium ii rain jacket review - the cinch featured on the helium ii did a fantastic job at keeping...
The cinch featured on the Helium II did a fantastic job at keeping the hood on our heads, regardless of how windy it was or what type of headwear we had on.
Credit: Ian Nicholson

A Note on Fit and Sizing

The Helium II runs slightly snugger than most and is one of the slimmest fitting jackets in our review. However, for most people, we still recommend your usual size unless you find that you are typically in between sizes; in this case, we would recommend sizing up. A 5'10" medium-sized 175 lb user ordered the medium size (and also wore a size medium in every jacket we tested) and it fit comfortably; however, it's worth noting that it was a little tight with a puffy jacket underneath, though a thick base-layer like a Patagonia R1 Hoody fit great. Our size large test jacket fit our 6 ft, 185-pound tester nicely. Thought it was slightly snug, the torso stayed put when climbing and reaching overhead.

outdoor research helium ii rain jacket review - the helium ii runs a little smaller than most jackets we tested...
The Helium II runs a little smaller than most jackets we tested, though unless you are truly between sizes or you know you are going to need to layer more than just a light fleece (Patagonia R1 or equivalent), then you don't need to size up.
Credit: Ian Nicholson

Pocket Design

Continuing with the minimalist design, the Helium only offers one Napoleon-style chest pocket. This isolated pocket is very functional and fits even a larger than average smartphone or similar sized item. It does feature a "stuff pouch" that (now) features a clip-in loop for secure attachment to a harness. While not having a pair of pockets to put your hands in is a small disadvantage, we think folks looking for the insanely low weight and minimal packed size won't find this missing feature to be a deal-breaker.


At 6.5 ounces, this is the second lightest model we tested. It remains one of the lightest overall waterproof models currently available. Other impressively light models were the Black Diamond Fineline (7.5 ounces), which was similar in overall design and offered a little stretch for improved mobility.


The lightweight 30D ripstop nylon face fabric on this piece stood up to abrasion surprisingly well; we have to admit that we didn't expect such a super light fabric to withstand as much abuse as it did. We wore this model rock climbing and ridge scrambling repeatedly, and the forearms are just starting to show some wear from the rough granite after several months.

The main benefits of this jacket - super lightweight and packable - do come at the expense of durability. The bottom line is the Helium II is less durable than most jackets we tested, though not by a significant amount. For folks who are mostly day-hiking or backpacking, the Helium is more than durable enough for hiking trails.

Looking for something on the other end of the durability spectrum? Consider the Outdoor Research Foray, Arc'teryx Zeta SL, or the Marmot Minimalist.

outdoor research helium ii rain jacket review - the helium ii was easily the most packable jacket in our review...
The Helium II was easily the most packable jacket in our review, being half the size (or smaller) than most other jackets we tested.
Credit: Ian Nicholson

Packed Size

This model packs away in an interior Velcro-closure stuff pocket and is easy to compress down among the smallest of all the models we tested. There isn't much difference in packed size between this model and the Black Diamond Fineline, but it was significantly smaller than other models we tested.

This is the perfect model to keep in the bottom of a hydration, day pack, or multi-pitch pack, so it's always there. Unexpected rain, wind, or cooler than anticipated weather - this little secret weapon handles them all. The latest version of the Helium does come complete with a clip-in loop to facilitate attaching to your harness (where previous versions lacked this feature).

outdoor research helium ii rain jacket review - the newest version of the or helium ii features a clip-in point for...
The newest version of the OR Helium II features a clip-in point for carrying on your harness while stuffed away in its pocket. We think this jacket is fantastic for climbing and any other time you would like to bring a jacket just in case.
Credit: Ian Nicholson


The hood on this rain jacket has a stiffened brim and a unique front to back elastic cinch cord with an external lock. The collar has a simple fabric tab at the chin and a nice large hang loop in the back. The Helium II does not have pit zips; with the waterproof chest pocket, it is the only jacket we tested with no means of ventilation. The stuff pocket on the internal left front side closes with a Velcro tab and doubles as a good stash spot for snacks, while the wrist cuff is very simple with elastic on the inner wrist. The elastic hem cinch has one cord lock on the right side, and the logos double as reflective patches on the left chest and left sleeve. There is no back-facing reflectivity.

outdoor research helium ii rain jacket review - the helium ii has a nice hang loop on the inside of the collar and...
The Helium II has a nice hang loop on the inside of the collar and waterproof zippers with easy to use pulls. No pit zips on this ultralight shell though, and the wrist cuffs aren't adjustable.
Credit: Brandon Lampley


This model is one of the most affordable of the ultralight jackets we tested. This model is more expensive than the Black Diamond Fineline but is an ounce lighter and a tiny bit more packable, but the Fineline is stretchier and offers slightly better mobility.

outdoor research helium ii rain jacket review - the helium ii fits over a climbing or bike helmet well enough, but...
The Helium II fits over a climbing or bike helmet well enough, but it isn't quite as helmet friendly as some other models we tested.
Credit: Ian Nicholson


The Outdoor Research Helium II is a rad ultralight rain and wind jacket at an excellent price. It's fine-tuned for light and fast activities that take advantage of its excellent mobility and respectable breathability. When you don't need the Helium II, its hardly noticeable in your pack or clipped to your harness. It isn't as durable, well-ventilated, or versatile as some other options, but for folks looking for the best ultralight jacket, this is it.

outdoor research helium ii rain jacket review - this model provides dependable waterproof protection in a tiny...
This model provides dependable waterproof protection in a tiny package. It's our go-to jacket for just-in-case protection when multi-pitch climbing.
Credit: Brandon Lampley

Ian Nicholson
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