One of the latest color options for the Helium II is pictured above. All specs and features of the jacket remain the same as the model we tested.February 2020
Outdoor Research Helium II - Women's Review
Our Analysis and Test Results
At half the weight and half the packed size of most the other jackets in our lineup, the Outdoor Research Helium II is hands-down the best choice for all your lightweight drizzly adventures, as it measured at a third of the size and weight of the bulkiest of the jackets we tested. To maintain its minimal dimensions, this jacket disregards many of the bells and whistles of the more complex jacket designs, giving you only what you need to stay protected from the weather and comfortable while on the move. With its Pertex Shield+ ripstop fabric, you get extreme breathability combined with a bit of added durability all rolled into a small functional package.
The Helium II uses Pertex Shield+ nylon fabric with a PU film laminate, which offers a sleek design and a great waterproof rating. We find more often than not, that what you gain in lightness you lose in water protection. Up against a moderate to light rain, and even when left with a puddle of water on top, the Helium does just fine. However, when tested in torrential downpours and a high-pressure spray in our simulated rain lab, the fabric will get wet.
This lack of performance makes this a better jacket for wearing as a just-in-case layer or for those on-again-off-again rain spittle days. If you find yourself in heavy downpours while pursuing your outdoor adventures, you may want to pick a different jacket. Nevertheless, it has several advanced features for added water resistance, like a crown cincher, to keep your hood in place, even in the wind or while moving around. The hood also features a stiff visor to keep your face shielded from the precipitation when things got intense.
The Helium is a great lightweight option as an outer shell over base layers; the featherweight material is soft, pliable, and smooth. It is a comfortable jacket for wearing out on a hike on a warm day with minimal layers or wearing while mountain biking over a warmer insulating underlayer, and its minimal design presents fewer opportunities for chafing or rubbing. The designers even added little bonus features, like a protective flap on the inside of the top of the zipper to keep your chin comfortable when zipped all the way up.
However, one of the drawbacks is the lack of hand pockets, so remember to bring gloves if you're wearing this in cold weather. Moreover, if you plan on moving around a lot in this jacket, it may not stay in place, but it will move with you, riding up if you wear it with a backpack or climbing harness. It also has one of the smallest hem drops of any jacket we tested and is just one inch longer in the back than the front. The sleeve cuffs aren't adjustable, but rather elastic all the way around, and a bit on the shorter side compared to others. We also recommend putting some thought into sizing up if you are planning on wearing over multiple layers. We tested the small, and although the slim design has a very flattering fit, it was a bit snug when putting over a multitude of base layers.
The Pertex Shield+ nylon material with a PU film laminate of the Helium II helps this shell rank amongst the highest in breathability. While this coat doesn't offer features like pit zips or a mesh liner, it doesn't need those, as the fabric is thin and air-permeable enough to keep you cool, even during extreme exertion.
However, on the flip side, it certainly won't keep you warm on a wintery day or against any serious wind, as it lacks even the slightest hint of insulation. But if you plan on just using this as a shell over layers to keep mist or light rain off, it will add an extra layer without the weight, to keep you dry and comfortable.
At first glance, the Helium II looks a little like a shiny plastic bag and is not the most rugged of all the jackets we tested. The Helium sacrifices a fair amount of durability to make it easier to take with you on all your outdoor adventures.
The thinness of the material is partially balanced by ripstop fabric, which we found to be reasonably durable. However, with lots of use, especially under a harness or your pack, the material did seem to lose some of its rigidity. We didn't encounter any holes or tears during our testing, just a worn-down feeling of the fabric with use over time.
Weight and Packability
The Helium II blows the competition out of the water here, coming in at a featherweight of just 5.2 ounces. The designers at Outdoor Research focused entirely on keeping this jacket light, unfortunately cutting down on weight sacrificed a bit of this jacket's ability to protect you from the elements and last through countless adventures. However, its lightness makes it perfect for long backpacking trips and for throwing in the bottom of your bag just in case you might need it. In fact, with its stuff sack, you can even clip it to your belt loop when traveling very light for the unforeseen drizzle you may encounter while out exploring.
When packed in its handy-dandy stuff sack pocket with a carabiner loop, this jacket measures a mere 4.5x4.5x3 inches (60.75 cubic inches), making this by far the most compact jacket we tested. This impressively small size helps to secure its place firmly as the best ultralight rain jacket. When tucked away in its stuff pocket, you can easily clip this shell to your belt loop for easy access or toss it in your backpack for later use. We also like the fact that the ripstop fabric doesn't hold too many creases when unpacked.
Falling just above the average price of jackets we tested, this raincoat offers a pretty good value for a lightweight rain shell. For anyone that doesn't care about bulk or weight, it is less of a value, since it trades this for water and wind protection. However, if you are an ultralight adventurer, you may not be able to find a better rain shell for your needs for the price.
By far the smallest and lightest ultralight jacket we tested, the Helium II is our Top Pick for Ultralight Adventures. It sacrifices some protection and features to keep things minimal but is still a great option for an emergency layer or anyone wanting to shed ounces. If you're heading out into unpredictable weather or considering an added layer to your backpacking adventures, this jacket is an ideal minimalist shell.