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.