Reward your hardworking legs with hardworking warmth. Made with superfine merino wool, these women's Artilect Boulder 125 leggings deliver softness, breathability and a prime warmth-to-weight ratio.

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Soft, warm and lightweight, the men's Patagonia Capilene Air base layer bottoms insulate even when wet, dry quickly and resists odors for days of use whether you're on the trail or the slopes.

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The women's Patagonia Capilene Air base layer bottoms insulate even when wet, dry quickly and resist odors, offering the greatest range of warmth and comfort of any Patagonia base layers.

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Layer smart for chilly adventures. Whether you're trekking through the forest or bombing down the slopes, the breathable, warm men's Patagonia Capilene midweight bottoms are an ideal base layer.

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Warm, breathable and quick-drying, the women's Patagonia Capilene Midweight base layer bottoms feature HeiQ® Fresh durable odor control for daily use.

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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 women's base layer bottoms keep you warm and dry in seriously cold weather during technical alpine routes.

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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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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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When layering for mild-weather adventures, start with the women's Smartwool Classic All-Season Merino base layer bottoms. They're made from lightweight jersey with a supersoft next-to-skin feel.

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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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When the mercury dips and your kiddo heads out to play, the kids' Smartwool Classic Thermal Merino base layer bottoms offer breathability, natural stretch and a layer of warmth for cold-weather fun.

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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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