Our Verdict
Our Analysis and Test Results
In our testing, the Outdoor Research Helium UL stood out for its incredibly low weight and great packability, making it an ideal emergency rain or wind layer for fair-weather missions. However, we also found its limited weather protection and durability harder to justify at this higher price.
Water Resistance
This was not a particularly strong metric for the Outdoor Research Helium UL, but context is everything: for quick afternoon thunderstorms, the Helium UL might be all you need to briefly stay protected. For bigger weather events, however, this might not be the right option.
The Outdoor Research Helium UL is half to a third the weight of our top weather-resistant options, and it simply doesn't have enough material to provide the best protection from the elements. Having said that, this ultralight jacket technically offers 2.75 layers of 15-denier nylon, with a Toray Dermizax membrane. In light drizzles, the Helium could handle as much as a few hours, but in more intense and sustained storms, we got wet in this layer in the shoulders and neck areas. This jacket might be a good fit for those fast and dramatic thunderstorms often occurring in the afternoons in places like the Rockies, as long as those storms are measured in minutes, not hours.
The Aquaguard zipper on the Outdoor Research Helium UL was impressively water-resistant and helped with the weather protection scores. The same zipper is also what Outdoor Research put in the chest pocket, which was a nice addition for any items you might want to keep at least partially protected.
Breathability
This lightweight layer actually breathes quite well. While it may have 2.75 layers of fabric, it is substantially thinner than most of the other jackets in the lineup, helping the Outdoor Research Helium UL shed more body heat than more traditional layers.
We were able to wear this layer fairly comfortably while on moderate hikes, and we loved it for damp mountain bike rides. While we wouldn't go out of our way to hike in this layer uphill, it was a nice windbreaker on exposed ridgelines or windy plateaus. The relatively trim fit kept us from wearing many layers under it, but that helped us avoid getting too sweaty.
Comfort and Mobility
The Outdoor Research Helium UL has a more relaxed fit than previous versions of the Helium, and it made for much nicer mobility. The next-to-skin comfort is a bit reduced with the painted/sprayed liner, but we still found it reasonably comfortable.
Ultralight jackets have a tendency to be slimmer fitting, with the general idea that less fabric equals less weight, but the Outdoor Research Helium UL had enough room for us to scramble, cast a fly fishing rod, or even do some climbing. If mobility is on your priority list, keep the Helium UL on your contenders list if the lower weather resistance isn't a deal-breaker.
Weight
The weight of the Outdoor Research Helium UL is truly phenomenal. This is one of the lightest jackets we've ever tested, even across multiple jacket categories. Naturally, the Helium UL came in at the front of the pack.
This featherweight layer weighs 5.6 ounces in a men's medium. This is two or three times lighter than almost all the other rain jackets we tested.
Its packability is similarly mind-blowing, and we always managed to squeeze it into our bags. For climbing missions, the entire jacket easily fits into its chest pocket, and it can be clipped to the harness with a carabiner. If a lightweight, portable layer is what you're after, this is the one.
Construction Quality
As expected, the lightest of jackets is not the most robust. Having said that, Outdoor Research engineered the Helium UL to be relatively feature-rich and packed as much durability into a 5.6-ounce layer as they could.
The face fabric of the Outdoor Research Helium UL held up well when sticking to trails and light-duty scrambling. When voyaging into dense brush or rock climbing, we had to be more careful not to snag branches or sharp rocks on the jacket. However, the drawstring systems in the hood and hem worked very well and were relatively durable. We were also happy with the zippers on this otherwise delicate layer, which performed fairly well even when grit got into the teeth.
Should You Buy the Outdoor Research Helium UL?
If you need a graduated windbreaker that can handle some light precipitation and block some wind, the Outdoor Research Helium UL might be just what you're looking for. It shouldn't be your “plan A” jacket for impending large storms, but it's great for those surprise rains on a day forecasted to be sunny.
What Other Rain Jackets Should You Consider?
If this expensive jacket is out of your price range, consider the Helly Hansen Loke, which is a fraction of the price and still weighs just over 8 ounces. If you're realizing you need a more legitimate rain jacket for frequent use, consider the affordable Patagonia Torrentshell 3L.
| Awards | Best Option for Minimalists |
|---|---|
| Price | $225 List Check Price at Backcountry |
Overall Score ![]() |
|
| Star Rating | |
| Bottom Line | An ideal jacket for ounce‑counters who want a just-in-case layer for brief storms |
| Pros | Ridiculously light and compact, useful minimalist features |
| Cons | Low weight compromises weather protection, not very robust, wallet-straining price |
| Rating Categories | Outdoor Research Hel... |
| Water Resistance (45%) | |
| Breathability (20%) | |
| Comfort and Mobility (15%) | |
| Weight (10%) | |
| Construction Quality (10%) | |
| Specifications | Outdoor Research Hel... |
| Number of Fabric Layers | 2.75 |
| Material and Waterproof Membrane | 2.75-layer Toray Dermizax 3D |
| Measured Weight | 5.6 oz |
| Pockets | 1 zippered chest |
| Pit Zips | No |
| Pit Zip Length | |
| Stows Into Pocket | Yes |
| Carabiner Loop in Stow Pocket | |
| Helmet Compatible Hood (Per Testing) | |
| Hipbelt Friendly Hand Pockets | N/A |
| Additional Features | Adjustable hood with brim wire, drawcord hem, shaped and bonded cuff |











