Stay cozy on chilly forest treks and snowy alpine adventures. An ideal choice for cool-weather quests, the men's Patagonia Capilene midweight zip-neck base layer top keeps you comfy on the move.

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Built to keep you warm and dry in seriously cold weather, the men's Patagonia Capilene Thermal Weight base layer bottoms have an open-grid pattern for warmth, breathability and moisture wicking.

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These base-layer bottoms keep you warm and dry in seriously cold weather during technical alpine routes.

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When a foot-wide ledge becomes your bed for the night, this compressible zip-neck helps turn up the heat.

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Whether you're skiing or heading out on a chilly hike, the men's Smartwool Classic All-Season Merino 3/4-Length base layer bottoms are ideal for year-round layering and comfy enough to wear all day.

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Built for 4 seasons, the men's Smartwool Classic All-Season Merino Base Layer bottoms keep you comfy on snowy days or summer nights under the stars with durable wool-blend fabric and an updated fit.

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With its soft and durable merino wool blend, the men's Smartwool Classic All-Season Merino long-sleeve base layer top is game for any adventure from spring skiing to winter hiking.

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Game for any adventure, any time of year, the men's Smartwool Classic All-Season Merino quarter-zip base layer top is made from a lightweight jersey and built for comfort—even under your pack.

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Whether you're skiing, hiking or running, Smartwool Classic Thermal Merino 3/4 base layer bottoms provide reliable comfort and breathability with an updated fit to minimize sag and keep you going.

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Updated with a better fit and reliable, resilient merino wool, the men's Smartwool Classic Thermal Merino base layer bottoms keep you comfortably warm through winter and all year long.

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Made from premium merino wool, the Smartwool Classic Thermal Merino Crew base layer top helps regulate your temperature with improved performance functionality while hiking or skiing in cold weather.

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Made of heavyweight merino wool, the men's Smartwool Classic Thermal Merino quarter-zip top helps regulates your temperature during high-intensity skiing, hiking, running and more in cold weather.

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Made of heavyweight merino wool, the men's Smartwool Classic Thermal Merino quarter-zip base layer top helps regulates your temperature during high-intensity skiing, hiking or running in cold weather.

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Made for all types of winter activities, this 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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