Designed to layer under shorts or pants, the women's Smartwool Intraknit Active base layer bottoms help with moisture management and temperature regulation to keep you comfortable while you're active.

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With mesh ventilation for cooling, a fit that moves with your body and minimal seams to help reduce chafing, the women's Smartwool Intraknit Active base layer top is ready to go the distance with you.

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Engineered 3D-knit panels of Merino Sport yarn deliver perfectly placed breathability and thermoregulating comfort on the women's Smartwool Intraknit Thermal Max Merino Pattern hoodie.

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With seamlessly integrated insulation and ventilation and articulated flex zones, the women's Smartwool Intraknit Thermal Max Quarter-Zip base layer top is made for high-intensity, cold-weather fun.

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Here to help you warm up to cold weather, Smartwool Intraknit Thermal Merino base layer bottoms have 3D-knit articulation that adds an enhanced fit and helps keep you as mobile as ever.

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Built to flex and follow you like a shadow, the women's Smartwool Intraknit Thermal Merino base layer bottoms are 3D knit for insulation, ventilation and flexibility for your high-intensity workouts.

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Keep your temperature just right on cold days with the built-in ventilation of the women's Smartwool Intraknit Thermal Merino Colorblock Quarter-Zip base layer top featuring body-mapped mesh zones.

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This minimalist Smartwool Intraknit Thermal Merino women's crew base layer top is lightweight and super-moveable—perfect for all of your sweatiest cold-weather activities.

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Highlight your base-layer comfort in floral. The women's Smartwool Intraknit Thermal Merino Pattern crew top is designed with targeted mesh-ventilation and a 3D-mapped fit to venture through the day.

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A good choice for cool-weather adventures, the women's Smartwool Intraknit Thermal Merino quarter-zip base layer top helps keep your body dry and comfortable—and the fit won't slow you down.

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Made of 100% merino wool, the Wild Rye Jane 7/8 Crop leggings are built to endure the rigors of long days in the mountains. They're cozy enough for apres, but technical enough for weeklong hut trips.

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A lightweight base layer with a shortened silhouette, the women's Wild Rye Jane Lite crop leggings will keep you warm (but not too warm) from spring skiing to summer camping.

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Looking for a base layer legging with a sleek, soft design? The women's Kari Traa Klara high-waist base layer pant has a slim silhouette with an extra-high, extra-comfy waist for added coverage.

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Combining a warm, breathable 100% merino wool exterior with a 100% LIFA® wicking interior, the Helly Hansen LIFA Merino Midweight Graphic pants are the perfect base layer for cold-weather pursuits.

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