Designed for lower output activities in cool temperatures, the women's Arc'teryx Rho Lightweight Hoodie base layer top is moisture-wicking, quick-drying, breathable and seriously soft.

Underwear TopsBase Layer Tops

Comfort starts with your base layer. Made for wicking and warmth on low-output days, the women's Arc'teryx Rho Lightweight zip-neck base layer top feels supersoft, moves with you and layers easily.

Underwear TopsBase Layer Tops

Skiing, backpacking or climbing, the Arc'teryx Rho Wool Long-Sleeve Crew women's base layer top is extremely versatile. It's fitted for easy layering, while stretch and articulation free up movement.

Underwear TopsBase Layer Tops

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.

Underwear BottomsBase Layer Bottoms

Knit with a Nordic-inspired floral design, the women's Kari Traa Rose half-zip base layer top is made from insulating merino wool for next-to-skin comfort, natural odor-resistance and breathability.

Underwear TopsBase Layer Tops

Built to support you through the most gravity-defying poses, the Beyond Yoga SD Lift Your Spirits bra keeps your flow distraction-free and your styling on point when you're hitting the mat.

UnderwearSports Bras

Your next-to-skin layers should always be extra comfy, which is why Smartwool makes the Seamless Racerback bra. A comfortable seamless merino wool interior combines with an outer designed for support.

UnderwearSports Bras

No more itchy seams and stifling fabric. The Smartwool Seamless Strappy bra feels is here to help you perform comfortably with engineered knit cups for shape, lift and hold during low-impact activity.

UnderwearSports Bras

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.

Underwear BottomsBase Layer Bottoms

Some wear it as a smoothing base for daily wear. Some wear it as a light and warm base layer under their gear. Either way, the women's REI Co-op Silk camisole makes a great foundation.

Underwear TopsCamisoles

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.

Underwear BottomsBase Layer Bottoms

Some wear it as a light and warm base layer under their gear. Some wear it as a smoothing base for daily wear. Either way, the women's REI Co-op Silk V-neck shirt is a great foundation.

Underwear TopsBase Layer Tops

Soft, cozy and naturally moisture-wicking, the Icebreaker Siren bikini underwear offer itch-free merino wool fabric in a modern, sleek fit.

Underwear BottomsBriefs - DEPRECATED

Made with a soft, durable merino blend to regulate body temperatures in all weather conditions, the Icebreaker Siren bra is lightly supportive and endlessly comfortable for easy everyday layering.

UnderwearSports Bras