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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Built to stretch with you and still retain its shape, the women's Artilect Boulder 125 Crew base layer top combines merino wool and nylon for an incredibly soft and durable fabric.

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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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Combining merino wool and nylon for an incredibly soft and durable fabric, the women's Artilect Boulder 125 Quarter-Zip base layer top stretches with you and still retains its shape.

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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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Comfy with light support, the Lole Burst bra is crafted from sweat-wicking and quick-drying fabric offered in classic racerback style.

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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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High performance in cooler months begins with a great base. Working from the inside out, the women's Craft CORE Dry Active Comfort base layer top is soft, functional and 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, naturally dry and odor-free, merino makes a perfect winter base layer. The Craft CORE Wool Mix base layer set provides comfort and warmth so you can train all day long in colder months.

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Built with perforated polyamide jersey fabric with printed reinforcements for enhanced pullback and stability, the Craft CTM Distance sport top is more than ready to go the distance.

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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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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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