New technical fabrics don’t come along very often, at least not from the biggest manufacturers, so when they do it’s worth taking a closer look. Polartec has just announced what they’re calling Power Shield Pro, and I was able to spend a few days skiing in it via The North Face Kishtwar jacket. Short verdict: I like.

Exactly what constitutes a softshell has been debated for years, and while I’m happy to argue definitions until last call at the bar at the Hotel Monaco, for practical use it’s about as relevant as the ratio of unicorns to leprechauns. In broadest terms, softshells are 1) soft, 2) stretchy, 3) highly breathable, 4) water-resistant, not waterproof. Hardshells are 1) not that breathable, 2) waterproof. Power Shield, which was introduced in 1998, relies primarily on a water-resistant coating to keep you dry; Power Shield Pro, which will be available at retail in fall, reinforces the coating with a microporous, water-resistant polyurethane membrane.

Membranes generally mean better water resistance at the cost of breathability—and this new Polartec product is more of the first and less of the second compared to its namesake predecessor—so the critical question to ask of Power Shield Pro is how well does it does just that, breathe. Fortunately, testing conditions at Mammoth Mountain were ideal for evaluating breathability: The days started cold, around 12 degrees, but by afternoon warmed to the high 30s.

And? The PS Pro was impressive. Rather than shed layers as the mercury climbed, the Kishtwar kept pace and vented whatever perspiration I worked up. Only once, when we hiked out the Dragon’s Back and jumped into the woods, where I buried a tip under a snag and fought for five minutes to get it out, did the sweat really pop. Back on Chair 9, I unzipped the jacket partway and by the time I was off the lift and standing on my skis I was dry. (Water resistance wasn’t tested; the skies were clear.)

As for the Kishtwar itself, the $279 piece is a nice, standard issue hooded jacket, with two giant hand warmer pockets and a generous Napoleon pocket. The four-way stretch was perfect. There was enough give for comfort, but not so much that a burrito in the pocket hangs at your waist. Power Shield Pro can be applied to many weights—the Kishtwar’s was light enough to serve as a spring shell or winter protection for 90 percent of your days. My test model was a preproduction model, with surprisingly little, for a sample, to quibble about, but TNF should consider lengthening the arms before it starts production.

Softshells are primarily supposed to keep you dry from the inside. Water resistance is important, but at some point the wet gets too wet and you put on a hardshell, so the greater issue by far is breathability. Although I’ve only had two days in it, from what I can tell Power Shield Pro is a winner on that front.