Update your cold-weather kit with tights that adapt to your activity. Smartwool Classic Thermal Merino base layer bottoms offer cozy warmth for stop-and-go activities and feature an improved fit.

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Serving up warmth for stop-and-go activities and an improved fit, the women's Smartwool Classic Thermal Merino base layer bottoms in plus sizes are a reliable, cozy addition to your cold-weather kit.

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Yoga-inspired leggings with ample stretch in the single-sided brushed stretch jersey knit, Obemeyer Courtnay leggings provide unrestricted movement and an active fit.

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A versatile winter essential, the girls' Obermeyer Courtnay leggings can be worn as a base layer on the mountain or casual pants back at the lodge.

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With soft, stretch cotton, comfort seams and non-friction areas, Kari Traa Dekorativ Hipster underwear feel smooth and breathable during any activity. This package of 2 offers fun colors of a go-to.

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Whether you layer them or wear them on their own, Obermeyer Discover tights offer a flatseam construction for comfort, a soft brushed interior and fun one-of-a-kind colors and prints.

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Great for layering to add warmth on active days out—or wearing solo cozied up in your tent—the women's Kari Traa Elenore base layer tights are made with soft wool for a comfortable next-to-skin feel.

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Offering superior temperature regulation without the bulk, tasc Performance Elevation Merino men's base layer bottoms deliver light warmth and moisture management for cool-weather outdoor activity.

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Offering superior temperature regulation without the bulk, the women's tasc Performance Elevation Merino base layer bottoms deliver warmth and moisture management for cool-weather outdoor adventures.

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Designed not to roll, ride up or constrict, the 3 in. inseam Patagonia Essential boxer briefs keep you comfortable from sunrise to sunset, with breathable, supersoft and chafe-free fabric.

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The 6 in. inseam Patagonia Essential boxer briefs keep you comfortable all day long with supersoft, chafe-free and breathable fabric and a design that never rolls, rides up or constricts.

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Supersoft, chafe-free and breathable fabric combines with a bulk-free fit and anti-roll waistband to make the Patagonia Essential boxers your go-to for all-day comfort.

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Our outdoor expertise doesn't stop at zip-off pants. The men's REI Co-op Everyday boxer briefs are built to traverse crags and run trails—or sit super comfortably while you plan those things.

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Our outdoor expertise doesn't stop at zip-off pants. The men's REI Co-op Everyday boxers are built to climb mountains and run marathons—or sit super comfortably while you plan those things.

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