Corbeaux Agent ¾-Length Leggings ($129)

outside(Photo: Inga Hendrickson)

The best bottoms are the ones you don’t have to think about. That’s the Agent. It moved moisture and never felt constricting as we skinned up and charged down. Credit the recycled polyester and spandex, with Tic Tac–size pockets that trap warm air.

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Adidas Outdoor Primeknit Long Sleeve Shirt ($79)

base layers(Photo: Courtesy Adidas)

Adidas debuted Primeknit in shoes and apparel in 2012, and we love the mix of light weight and durability. This layer is seamless (read: no chafing under pack straps), with sections of polyester, polyamide, and elastane for stretch.

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Smartwool Smartloft-X 60 Hoodie ($250)

base layers(Photo: Courtesy Smartwool)

The Smartloft-X is our favorite men’s ­midlayer this year. A stretchy merino blend at the arms and back dumped heat on the skin track, while recycled wool in the chest was plenty toasty. The perfect piece for nights around the fire on a late-winter camping trip.

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Kari Traa Alelam Pants ($90)

base layers(Photo: Courtesy Kari Traa)

All good base layers keep you warm and dry. Kari Traa’s lightweight Alelam accomplishes that with wicking, odor-resistant merino and mesh panels behind the knees. But the best ones are cozy, too. Here, sweatshirt-style knit cuffs make these tights feel more like PJs.

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Montane Primino Hybrid Hoodie ($100)

base layers(Photo: Courtesy Montane)

Hooded underlayers can feel claustrophobic. Not the merino-poly Primino, which blends in PrimaLoft and has breathable mesh at the chin, so you don’t drown in condensation. (The same material is on the back and underarms for stellar sweat management.)

Men's Women's

Backcountry Wolverine Cirque Insulated Jacket ($230)

base layers(Photo: Courtesy Backcountry)

The Wolverine Cirque is for those of us who can’t decide what kind of midlayer to wear: synthetic fill warms the core, while stretch fleece along the sides, under the arms, and at the hem and cuffs permit movement. It has the warmth and heft of a puffy, and the interior won’t slip and slide over other layers.

Men's Women's

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