Bottom Line
The Outdoor Research Helium’s (men’s / women’s) main appeal is extremely low weight: at just 5.7 ounces, it fits trips where every ounce of emergency weather protection matters. With no dedicated vents, however, it is less adaptable for warm, high-exertion climbs.
Its limited ventilation and lightweight construction involve compromises compared with more substantial shells, reflecting the compromises of this minimal design. Choose it for weight-sensitive outings rather than treating it as a full-featured everyday rain jacket.
For more options, see our Best Rain Jackets guide.
How We Tested
Tested against Alaska’s toughest elements—rain, sleet, and snow—this jacket has proven itself on strenuous hikes through relentless wet weather. For every rain jacket we review, we push it to the breaking point to see how well it holds up to moisture and identify the specific conditions where it performs at its peak.
Quick Specs
Outdoor Research Helium
Most Affordable Ultralight Rain Jacket
CleverHiker Rating: 4.3/5.0
Price: $170
Listed Weight: 5.7 oz.
# of Vents: 0
Pros
- Extremely light
- Low packed weight
- Useful minimalist backup shell
Cons
- No dedicated vents
- Less durable than heavier options
- Limited heat-management choices
Comfort & Mobility
The Helium UL is designed around light carrying weight rather than plentiful comfort features. On the earlier Helium, our testers appreciated a trim fit and enough room for a lightweight puffy, though the fabric offered less stretch than some competing shells. Its elastic wrists worked reasonably well despite lacking precise cuff adjustments. Try the UL over your usual layers to assess its fit for extended wear.
Comfort & Mobility Score: 4.4/5.0
Weather Resistance
The UL’s current weather-resistance score favors a lightweight emergency shell over a burly all-day storm jacket. The earlier Helium performed usefully through a wide range of trail storms, including difficult wet weather in Alaska, yet CleverHiker observed that its protection declined faster in persistent downpours, especially beneath backpack straps. The UL is most appealing as a lightweight backup rather than a heavy-duty storm shell. It gives shoppers a concrete reason to prioritize a more substantial three-layer shell when prolonged saturation is likely.
Weather Resistance Score: 4.3/5.0
Ventilation
With zero dedicated vents, the Helium UL gives active hikers few ways to shed moisture without opening the front zipper. Our previous Helium testing illustrates the importance of this compromise: the older 2.5-layer shell frequently felt clammy and sticky during high-output efforts, and removing pit zips meant unzipping the front was the main ventilation option. The UL’s lack of dedicated vents is a tradeoff worth weighing against its very low weight.
Ventilation Score: 3.8/5.0
Durability
The UL’s current durability score sits below more substantial rain shells, making careful use a sensible expectation. Our older Helium showed a revealing distinction between fabric integrity and weather resistance: the 30-denier shell showed little visible wear, yet the water-repellent performance declined after repeated soakings. For frequent brush contact and extended storms, a burlier three-layer jacket is a better choice.
Durability Score: 3.9/5.0
weight
Our Helium UL weighed just 5.6 ounces. Our experience carrying the earlier Helium on long-distance hikes reinforces the appeal of an exceptionally light rain layer. It takes minimal room in a pack or running vest. The Montbell Versalite is a particularly relevant alternative because it remains light while providing pit zips.
Weight Score: 4.7/5.0
Should You Buy the Outdoor Research Helium?
The Helium UL is a specialist piece for hikers who want very low weight and can accept a pared-down feature set. At just 5.6 ounces, its most defensible advantage is having a shell available without carrying much mass.
It is not our recommendation for hot, high-exertion hiking in sustained rain because there are no dedicated vents. The Montbell Versalite gives weight-conscious travelers pit zips and a different balance of features.
What Other Rain Jackets Should You Consider
If you want ultralight but need a little more protection, check out the other similar options from our list of the best rain jackets.
Montbell Versalite Review: The Versalite includes pit zips while keeping weight low, making it a better match for active hikers who regularly need to dump heat. It weighs a little more than the Helium UL.
REI Rainier Review: This is an economical shell with a fuller set of adjustments and pockets. It is much heavier and less appropriate for hikers chasing the absolute lowest pack weight.
Zpacks Vertice Review: The Vertice is another ultralight shell, but adds pit zips for more heat control. It is worth considering when ventilation matters as much as minimal pack weight.
