With a form-hugging fit, the Smartwool Classic All-Season Merino Lace long-sleeve tee is a great first layer for high-energy activities—like hiking, jogging or rowing crew—in cool or warm weather.

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Made from a lightweight jersey, the women's Smartwool Classic All-Season Merino long-sleeve base layer top is just as comfy layered under your ski jacket as it is worn alone for summer backpacking.

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Made from their lightest-weight jersey and built for comfort, the women's Smartwool Classic All-Season Merino quarter-zip base layer top is game for any adventure, any time of year.

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Designed to be your go-to for warm or cold weather, the women's Smartwool Classic All-Season Merino quarter-zip top features lightweight, soft merino wool with a nylon core for increased durability.

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Delivering exceptional performance and improved functionality, the women's Smartwool Classic Thermal Merino crew top maintains your warmth and active comfort as you hike, ski, bike and more.

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Whatever high-intensity activity you get into, the women's Smartwool Classic Thermal Merino quarter-zip top delivers exceptional performance and improved functionality to keep you warm, dry and comfy.

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Stay comfortable, dry and warm in the plus-size Smartwool Classic Thermal Merino quarter-zip top while enjoying your favorite activities year-round. An improved, active-minded fit is designed to move.

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Made for all kinds of winter activities, the women's Craft Core Dry base-layer set has flatlock seams that enhance your comfort while the brushed jersey interior offers optimal warmth.

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Built for any exercise in cold-weather conditions, the women's Craft Core Warm base-layer set uses flatlock seams to enhance your comfort while the brushed jersey inside offers optimal warmth.

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Whether you layer it or wear it on its own, the Obermeyer Discover base layer crew top offers a flatseam construction for comfort, a soft brushed interior and fun one-of-a-kind colors and prints.

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Whether you're carving through the snow or walking through town, the women's Obermeyer is an ultra-light base layer designed to move with your body, excelling in any conditions, on any mountain.

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Thanks to its merino wool fabrication and flatlock construction, the Kari Traa Elenore women's long-sleeve base layer top feels cozy and comfy next to the skin, no matter the activity.

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Look no further for that perfect base layer. The women's tasc Performance Elevation Merino T-shirt offers superior temperature regulation and moisture management without the bulk.

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Let it snow! The women's Kari Traa Else Half-Zip base layer top blends soft merino wool and modern fabric mapping to keep you warm and comfortable on or off the slopes.

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