Shred to your heart's content with the comfort of these men's Midweight X base layer bottoms. They're your quiver-of-one, serving up quick-drying, stink-free warmth for long days on the mountain.

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Hit the lifts with all you've got. The women's Burton Midweight X base layer pants move right along with you with breathable, quick-drying fabric—plus, a media port stashes your phone for easy access.

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Crafted in a quick-drying mixed fabric blend that wicks moisture away from your body when the intensity rises, Kari Traa Perle base layer pants are a 4-season favorite.

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A great pick for summits in the spring and misty morning runs in the fall, these men's Saxx Quest base layer tights will move with you and take on whatever your day has in store.

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Worn as a technical training base layer for outdoor activities, Threads 4 Thought Ramsay Sports ReActive tights are soft and stretchy and have all the tech qualities you seek.

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Built for cold, on-the-move days, the women's Arc'teryx Rho Heavyweight base layer bottoms are highly stretchy and pair a durable, smooth face with a soft, brushed interior for warmth and wicking.

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When it's cold out, the men's Arc'teryx Rho LT bottoms are your lightweight thermal base layer for low and medium output. They add warmth, move moisture and feel soft on the skin.

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On cold days with lower output, layer up in the women's Arc'teryx Rho Lightweight base layer bottoms. Made for wicking and warmth, they dry quickly, let skin breathe and deliver soft-brushed comfort.

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Made with a textured knit with peached finish for first-layer warmth, the Saxx Roast Master Midweight base layer bottoms keep you warm whether you're carving turns or dodging snowballs.

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With beautifully detailed patterning and a soft merino wool fabrication, Kari Traa Rose base layer bottoms go beyond basic and are perfect for cold-weather activities.

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Whether under your hiking kit or just under jeans around town, the women's REI Co-op Silk bottoms make a great foundation as temps start dropping.

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The REI Silk long underwear bottoms are smooth, soft and incredibly comfortable. They'll help keep you warm on a cold day and they work great under additional layers.

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The REI Silk long underwear bottoms for women are smooth, soft and incredibly comfortable. They'll help keep you warm on a cold day and they work great under additional layers.

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With low-profile seams to minimize bulk and maximize comfort, the women's The North Face Summit Pro 120 tights are an adventure-ready, lightweight base layer made for any cold-weather exploration.

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