Comfortable across seasons, the men's Arms of the Andes 300 Lightweight Alpaca Wool leggings withstand tough environments and keep you warm in winter and dry in summer.

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Crafted from the softest Peruvian alpaca wool, the women's Arms of the Andes 300 Lightweight Alpaca Wool leggings withstand tough environments and help keep you comfortable in any climate.

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For hard training sessions and active lifestyles, these Craft Active Intensity base layer pants help you regulate your body temperature for extended comfort no matter what you're planning to conquer.

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For hard training workouts and active lifestyles, Craft Active Intensity women's base layer pants help you regulate your body temperature for extended comfort no matter what you plan to conquer.

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

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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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