Arc’teryx Proton LT Hoody | Preview - Outdoors Magic

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Down and Insulated Jackets

Arc’teryx Proton LT Hoody | Preview

Revised for 2019, the Arc'teryx Proton LT is a jacket you'll never want to (or need to) take off...

Active insulation. It’s a fascinating innovation, the kind of stuff that achieves the seemingly impossible task of keeping you warm when you’re stood still or going steady, and cool when you’re working hard.

The new revised version of the Arc’teryx Proton LT Hoody is one such garment to feature this clever tech. What we have here is a jacket with an air permeable outer fabric and a breathable synthetic insulation, a combination that makes it ideal for things like ski touring and winter climbing or walking.

It’s a piece of kit designed with absolute versatility in mind, serving as a standalone jacket that you won’t need to take off during aerobic activities, or as part of an insulation layering system, going under a shell when things get really rough.

We were able to try out Arc’teryx’s active insulation earlier this year when we tested their fast and light version of this jacket, the Proton FL. That product actually impressed us so much that it made it into our round-up of the best midlayers in 2019. Now for this autumn/winter, they’ve brought the same concept into this heavier-weight jacket; one that’s warmer, more durable and, crucially, that’s still as breathable.

Technical details

So how does the Proton LT Hoody tick so many boxes? Let’s start with the fabric, which is called Fortius Air 20. It’s this slightly stretchy material that keeps the jacket breathing, allowing hot, moisture-laden air to pass through its microscopic holes and out and away from your body. But it’s also extremely durable as well, much more durable than similar synthetic jackets. In fact, Arc’teryx say that the material proved 60 times tougher than the industry standard when put through their abrasion tests.

The main ingredient, however, is of course that Coreloft Compact active insulation. This stuff feels a lot like down, and isn’t far off it in the warmth-to-weight ratio stakes, offering a lofty, warm feel. It’s highly compressible as well, meaning you can bundle the jacket up into a nice neat little package when you want to slip it in your daypack.

To keep the overall bulk down, Arc’teryx have used a couple of interesting techniques. For instance, an 80gm/2 fill is used in the torso and 60gm/2 is in the hood where it’s not needed so much. They’ve also used a special reduction process which cuts the thickness of the material by 50% (in comparison to the previous Proton LT), with only a 10% loss in warmth.

Arc’teryx are a brand with mountain activities at the heart of what they do, and unsurprisingly this is reflected in the Proton LT’s feature set. The hood, for instance, can be worn over a climbing helmet, the cinch on the hem is designed so that the excess cord won’t snag on your equipment, there’s a pocket on the chest for stowing small items while you’re wearing a harness, and finally, a DWR coating provides shield from light rain or snow during those alpine ascents.

Final things to note include the low-profile stretch cuffs, ‘no slip zips’, its heaps of articulation, and a generally athletic fit. 

Who’s It Suitable For?

As we’ve touched upon, the main focus is probably going to be on performance during mountaineering, but we could see this layer becoming extremely popular with any type of mountain goers, whether they’re crag climbers, hikers or ski tourers.

Put it on at the start of the day, keep it on during the ascent, keep it on during the descent as well, and chuck a shell over it when the conditions get really rough. This is one of those jackets you’ll get a whole lot of use out of. So, if you’re in the market for a new puffy, an active insulation piece like this could really be the answer.


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