Your active, high-intensity lifestyle calls for the Craft Active Intensity base layer top. Wear this bestseller for training, running and skiing, whether it's cross-country or backcountry.

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Your active, high-intensity lifestyle calls for the Craft Active Intensity zip base layer top. Wear this bestseller for training, running and skiing, whether it be cross-country or backcountry.

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Ideal for everyday wear and active pursuits alike, the Icebreaker Anatomica boxer briefs are made with ultralight merino wool for warmth and all-day comfort.

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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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Face every challenge with the men's Artilect Boulder 125 Crew base layer top. It combines merino wool and nylon for an incredibly soft, durable fabric that stretches with you—and retains its shape.

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Dump heat—or add more—with the thermoregulating ventilation of the men's Artilect Boulder 125 Quarter-Zip base layer top. It stretches with you and keeps its shape after all your adventuring.

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Worn as a technical training base layer for outdoor activities, the Threads 4 Thought Brennan base layer long-sleeve quarter-zip top is soft and stretchy and has all the tech qualities you seek.

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High performance in cooler months begins with a great base. Working from the inside out, this Craft CORE Dry Active Comfort base layer top is soft and functional—essential to your winter gear.

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Soft, warm, naturally dry and odor-free, merino makes a perfect winter base layer. The men's Craft CORE Wool Mix base layer set provides comfort and warmth for all-day training in colder months.

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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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Lightweight, soft and warm, the men's Patagonia Capilene Air base layer hoodie insulates even when wet, dries quickly and resists odors for days of use whether you're on the trail or the slopes.

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Lightweight, soft and warm, the men's Patagonia Capilene Air crew base layer top dries quickly, insulates even when wet and resists odors for days of use whether you're on the slopes or the trails.

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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 for daily wear, the men's Patagonia Capilene Midweight Crew base layer top incorporates HeiQ® Fresh durable odor control to cut the funk and keep the fabric fresher.

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