When leaves start to change and cooler weather takes hold, the art of layering becomes key in outdoor adventure. Finding the perfect layering formula can be expensive and even frustrating. Thankfully, I’ve found a great one.
If I had a dollar for every time I didn’t want to stop and shed a layer, only to find myself sweating minutes later, I’d have many, many dollars. With expense and frustration in mind, I wanted to explore how the layering game could evolve.
That’s why I tested the Kor AirShell Warm Jacket from Mountain Hardwear — so you can hit your objectives in the mountains without the frustration of layer season.
In short: The Mountain Hardwear Kor AirShell Warm ($200) is one of our new must-haves for cool-weather adventures that satisfies with balance. Durable, feature-full, and lightweight, this new favorite has the remarkable ability to keep you warm when standing still but allows airflow when on the move.
Mountain Hardwear Kor AirShell Warm Jacket Review
The Inside
I tested the Kor AirShell Warm in what can only be described as perfect conditions to explore the world of layering. From climbing the Grand Teton in snow and rain to exploring the groves of changing leaves in Aspen, and hiking along ridges around Lake Tahoe, the airmesh lining of the Kor AirShell Warm kept the need to shed or add layers at bay.
Airmesh, Mountain Hardwear’s choice material here, is a durable mesh made of hollow quick-drying fibers. Think of combining mesh and a fleecy material — it creates a perfect blend of retaining heat when standing still but also has the ability to dissipate heat when moving.
Perfect for aerobic activities like ski touring, trail running, or hiking, the Kor AirShell Warm remarkably allows airflow when active but provides warmth when taking a break. No need to stop to shed layers — this jacket was built to keep you moving.
The Exterior
When I was climbing up the Grand Teton, it’s safe to say I rubbed against a rock (or 50 — who’s counting?). Thankfully, the shell fabric proved extremely durable. (And that’s with a 59% recycled fabric!) The outside of the AirShell Warm is crafted with a lightweight and breathable stretch ripstop called Pertex Quantum Air fabric.
Light, packable, and weather-resistant, I stayed warm and dry during light rain while hiking up to high camp. Through aspen groves and up multipitches, I have yet to cause a tear, regardless of how many objects I walk into, brush up against, or slip down. (Hey, it happens!)
Most importantly, the outer fabric is air-permeable, which allows for a mechanical transfer of air both into and out of the shell. Just another reason this might be the last jacket you’ll need when hitting the trail — you’ll feel comfortable when your body is working hard when normal fabrics might leave you feeling damp. Yes, please.
Jacket Construction
The features on the Mountain Hardwear Kor AirShell are seemingly endless, which makes this jacket’s abilities more than just ending the layering qualm. Two zippered hand pockets and two zippered chest pockets mean there’s extra room for everything you need on a trail or when traveling. Zippers ensure that everything stays safely stowed away — no more lost keys or micro trash on the loose.
Thoughtfully placed details make comfort a priority with the Kor AirShell Warm. The jacket employs elastic where heat retention is a must, like at the cuffs and along the hood. A drawcord hem keeps the jacket fitted to prevent riding up when working hard, and a two-way front zipper allows you to release heat, without ditching the Kor.
Coming in at only 11.3 ounces, the Mountain Hardwear Kor AirShell Warm is able to do everything a lot, while being so lightweight.
Mountain Hardwear Kor AirShell: Conclusion
The balance of layering is hard. We’ve all fallen prey to leaving a too-warm layer on, and then sweating, followed by shivering. But constant delayering and relayering no more: the Kor AirShell Warm allows for both warmth and breathability. And while many other jackets we’ve tested do that also, this one has a great balance of the two.
When leaves change and snow begins to fall, you’ll catch us on the trail in the Mountain Hardwear Kor AirShell Warm.
