The winter-ready pants you need to perform all season, the men's Smartwool Intraknit Thermal Merino Base Layer 3/4 Bottoms use merino wool to help keep you comfortable on every cold-weather outing.

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Built to flex and follow you like a shadow, the men's Smartwool Intraknit Thermal Merino base layer bottoms put warmth first, while 3D knit mesh ventilation helps keep you dry and comfortable.

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Here to help you warm up to cold weather, Smartwool Intraknit Thermal Merino base layer bottoms have 3D-knit articulation that adds an enhanced fit and helps keep you as mobile as ever.

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Built to flex and follow you like a shadow, the women's Smartwool Intraknit Thermal Merino base layer bottoms are 3D knit for insulation, ventilation and flexibility for your high-intensity workouts.

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Made of 100% merino wool, the Wild Rye Jane 7/8 Crop leggings are built to endure the rigors of long days in the mountains. They're cozy enough for apres, but technical enough for weeklong hut trips.

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A lightweight base layer with a shortened silhouette, the women's Wild Rye Jane Lite crop leggings will keep you warm (but not too warm) from spring skiing to summer camping.

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Looking for a base layer legging with a sleek, soft design? The women's Kari Traa Klara high-waist base layer pant has a slim silhouette with an extra-high, extra-comfy waist for added coverage.

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Combining a warm, breathable 100% merino wool exterior with a 100% LIFA® wicking interior, the Helly Hansen LIFA Merino Midweight Graphic pants are the perfect base layer for cold-weather pursuits.

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Naturally odor-resistant with mesh ventilation to help prevent you from overheating, the women's Kari Traa Lam base layer pants have a supersoft feel for next-to-skin comfort in any season.

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A go-to base layer for winter play, these Kari Traa Lam base layer pants are a supersoft, supersmooth pair of merino wool leggings with ergonomic lines for a pro-sport look.

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Make your first layer a comfortable one with the men's Picture Organic Clothing Lhotse base layer pants. They feature chafe-free seams and a nonirritating elastic waist band.

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Fend off the chill and stay out longer in the men's Helly Hansen Lifa Merino Midweight base layer pants. Built for winter fun, they blend merino wool with technical fabric to keep you cozy and warm.

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These REI lightweight base layer bottoms are designed to keep you warm and wick away moisture during high-performance outdoor activities when the temperature starts to drop.

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From morning's first frosty steps to midday sweat and exhilaration, the men's REI Co-op lightweight base layer bottoms wick and breathe to keep you comfortable all the way.

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