Testing Stio’s New Power Wool Base Layers

Made from a blend of merino wool and synthetic, they perform great and don't shrink in the wash


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This season, Stio teamed up with Polartec to create a line of base layers from a new fabric called Power Wool. Aimed at combining the best qualities of both merino wool and synthetic fibers, the fabric features a layer of soft, moisture-wicking merino wool on the inside while a synthetic outer layer adds strength and durability. The result is a base layer that’s breathable, comfortable, moves moisture, and will last for many seasons. 

To test out the new fabric, I wore Stio’s Basis Zip Neck baselayer ($110) during a four-day ski trip to Eiseman hut, a 10th Mountain Division hut located seven miles into the backcountry outside of Vail. The Basis was the only baselayer top I brought and except for sleeping, I wore it for everything from skinning, to lounging, to making dinner. It was awesome. 

I love zip neck base layers and the Basis' high neck provided a little extra protection from the elements and also helped prevent chafing from the strap of my avalanche transceiver around my neck. Gorgeous weather, with temps in low 50's, meant the skin track was a sweaty affair, especially during the seven-mile approach to the hut while carrying a 40-pound pack. By the end of the trip, I didn't smell great and my midlayer, an Outdoor Research Uberlayer smelled downright awful, but the Basis was completely odorless. This is a testament to the antimicrobial properties of wool but also Power Wools ability to move moisture and dry quickly. 

While I was impressed with the Basis' performance, I was most excited that after washing and drying it after the trip it maintained its shape and didn't shrink like most of my other merino wool base layers. 

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