Recommended Down Jackets : Arc’teryx’s lightweight Cerium LT

The Arc’teryx Cerium LT Down Hoody is no exception. It’s a premium down jacket that is super warm for its weight, thoughtfully designed, and beautifully constructed.

Arc’teryx’s lightweight Cerium LT : Performance

The Arc’teryx Cerium LT uses a unique hybrid insulation with high quality down fill around the core and synthetic fill under the arms, around the sleeves, and along the shoulders. Thankfully, Arc’teyx’s decision to use this mixture in no way sacrifices the plush warmth down jackets are well known for. In testing we found it provides very similar levels of warmth to the Ultralight Hoody from Patagonia and is more insulated than the popular Mountain Hardwear Ghost Whisperer.

None of these can compare to a full-on winter down jacket and are all a bit less insulated than heavier down sweaters, but they bring greater packability and warmth for their relative weight. The wind resistant shell on the Cerium LT performed well on some cold day hikes and in use in a variety of snow sports, but would fall short as a belay jacket in truly frigid and wet conditions (for those conditions, we prefer the synthetic Arc’teryx Nuclei AR). To really bundle up or if it’s very windy, throw it on under a shell for subfreezing comfort. The jacket’s insulated hand warmer pockets were appreciated when we weren’t on the move.

Arc’teryx’s lightweight Cerium LT :  Materials and Construction

We do feel it’s worth mentioning that some users have reported that their Cerium LT is prone to shedding down, but we have not seen any undue loss of feathers. We’ve had to massage a few back through the fabric that were attempting to escape, but it’s overall been a very normal experience.

By keeping a bit of heft, the feel of the outer shell is plusher than most other ultralight options. The hand feel struck us as a more substantial version of the Patagonia Ultralight, and that’s a compliment, as both were smooth and had a nice next to skin softness on both the outer and inner shell fabrics—including the collar in front of the face when fully zipped. A common place to cut some weight is through lighter weight zippers, and Arc’teryx makes use of those on the main zipper as well as two hand pockets. While they are noticeably lightweight, all zippers are nonetheless confidence inspiring and we have experienced no hiccups.

Premium materials and fit and finish are areas where the Cerium really excels. Excellent stitching and very clean lines are present in every Arc’teryx product we’ve had our hands on. It’s extremely rare to find even a loose thread on these jackets, something that you can’t say of most outdoor brands.

Arc’teryx’s lightweight Cerium LT : Weighing the Cerium LT

With a total weight of 10.22 ounces (including the .21 oz. stuff sack) in a medium size on our scale, the Cerium LT Hoody is unquestionably a lightweight down jacket. But within the ultralight category we tested it against, it does fall on the heavier end. The Montbell Ex Light (6.31), Mountain Hardwear Ghost Whisperer (7.68 oz.), and even the Patagonia Ultralight Hoody (10.05 oz.), are lighter. It’s important to keep in mind that the Cerium LT uses a heavier weight shell fabric than those jackets and has some synthetic insulation in select panels. These features offer tangible benefits (discussed later on) but also add a little weight. And, let’s be honest, 10 ounces for a warm insulating piece is still extremely light.

Arc’teryx’s lightweight Cerium LT : Down Composite Mapping

Although there is some synthetic insulation in the jacket, primary heating duties are reserved for the down. And Arc’teryx uses super lofty 850-fill-power white goose down in the Cerium. Fill weight is the actual amount of down used inside the jacket, and the Cerium LT Hoody has 3.35 ounces, which is quite a bit for such a light jacket, and is pretty comparable to the Patagonia Ultralight (3.52 oz.). Total fill weight is elusive with the Cerium because of its dual insulation, but it’s safe to say there’s a healthy amount of down in the jacket.

Synthetic insulation is measured based off of how much a 1 x 1 meter section of the insulation weighs. The 80-gram weight used in the Cerium is on the warm but not extremely warm side, balancing the added weight of synthetic with solid insulating properties that continue to perform well when wet. The system is a good one, and the different insulation is unnoticeable in daily use. It’s still not designed to be a jacket you’d wear in heavy rain, so still bring a shell to wear over if the weather turns, but the synthetic does bring additional confidence in backcountry use and around snow.

You may also like to read about  Recommended Men’s Down Jackets of 2018

The number one enemy of down is moisture. Unlike synthetic jackets, when moisture reaches the down clusters, it turns them to a mush, compressing their loft. The loss of loft means the down no longer insulates. To combat this, Arc’teryx chose a high quality synthetic, Coreloft, in the areas of the jacket most prone to getting wet: shoulders, underarms, cuffs and collar in front of the mouth. Down is retained in the areas where maximum heating efficiency is enjoyed: the core, hood and upper arms.

Arc’teryx’s lightweight Cerium LT : Fabric Denier Rating

In their construction, Arc’teryx opted for a 20x10D ripstop nylon, which means a combination of heavier 20D fabric with ultralight 10D. By mixing fabric thickness and weight in the construction, Arc’teryx is able to bring extra durability, while still cutting some weight. Hand feel of the shell is still relatively thin, so a bit of extra care is always a good idea, but it definitely was more confidence inspiring than the 7D shells found on jackets like the Ex Light or Ghost Whisperer. And we’ve experienced absolutely zero durability issues over extensive use of the jacket.

Arc’teryx’s lightweight Cerium LT : Stuffing it Down

The mix of down and synthetic, while appreciated for its wet weather performance, had us a bit concerned it might come at the sacrifice of compressed size—a big reason to opt for a down jacket in the first place. Well, we’re happy to report that our concerns were completely unfounded. The Cerium stuffs down quite easily into the included stuff sack, measuring approximately 8.5 x 4.5 x 5 inches (LxWxH of the cylinder shape), a size that stacks up well with its primary competitors.

We much prefer down jackets that stuff into their own pockets, but Arc’teryx did make an effort to address the primary reason to avoid a stuff sack: losing the bag. With a loop on the inside of the right hand pocket, you can simply tie the stuff sack to that spot. It’s simple and works well, and the only downer is you still have to carry around a stuff sack in your pocket (unless you have a good storage alternative).

Arc’teryx’s lightweight Cerium LT : Sizing and Fit

Trim fit is how Arc’teryx describes the jacket’s cut, and we can strongly confirm that designation. We had a medium for testing, and while the sizing was true, it had the most athletic cut of our entire lightweight down jacket test—something we really appreciated with a pack on when extra bulk under a pack’s straps can cause some discomfort. Trim at the waist and no hem adjustment means that if it doesn’t fit there, you’ll be in a bit of trouble (note: Arc’teryx has added an adjustable waist cinch for 2017-2018). The hem does have some elasticity, and doesn’t have a tendency to bunch up, so it will still fit most athletic body types. It’s the kind of jacket that moves with you, as opposed to feeling like you’re swimming around inside of it. Further contributing to this feeling was a streamlined but comfortable fit in the shoulders, midsection and sleeves.

The Cerium falls on the shorter end, with a back length measured at 25.75 inches (medium size). It’s within a quarter inch of the similarly short Patagonia Ultralight, but is a full 2-inches shorter than the Ghost Whisperer—something to consider for the long torso-ed crowd. But that lines up well with the intended use for this jacket—primarily as a mid layer. That being said, our 6’1” tester had no complaints about the jacket being too short thanks in part to its well-tailored fit.

The cuffs are low profile and really well integrated into the sleeves—making them our consensus favorite design in the whole group. An internal cuff allows the fabric and insulation to cover the entire wrist. A similar concept is used in the Ghost Whisperer, but it sits awkwardly over the wrists. No problems with the Cerium LT. There also is sufficient stretch to fit over gloves if needed, but they aren’t so loose to let cold air seep through.

Arc’teryx’s lightweight Cerium LT : Hooded and Non-Hooded Versions

The Cerium is made in both hoody and standard jacket designs. And if you need help deciding, read our article: Does Your Down Jacket Need a Hood? If you opt for the head coverage, you’re getting, in our opinion, the best system currently on the market. The large, but not helmet compatible, StormHood cinches just like most other down jackets, with a single drawcord on the back of the hood. But in contrast to the rest, it cinches evenly all around your head, uniformly securing around your forehead and back of your melon. It’s a seemingly simple feature, but one that further shows the level of detail and care Arc’teryx takes in designing their products.

The Cerium LT isn’t the lightest jacket in our test, and it’s not even the lightest in the Cerium family (the Cerium SL is where you go for a sub-7-ounce piece). But it, along with the Patagonia Ultralight, were our favorites from the super light category. Parsing the differences between the two mostly came down to fit (they also finished in the top 3 in our article of the best down jackets), with the Ultralight feeling roomier and more ready to handle a thicker layer underneath, at the sacrifice of a boxy cut. The Cerium can handle a thin fleece at most, and is clearly designed with an athlete in mind. But that athlete isn’t always on a mountaintop, and the Cerium brings warmth and comfort to the daily doldrums. A true crossover performer, the Cerium LT is a winner in our book.

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