Men's Intraknit Thermal Merino Base Layer Crew

3D-Knit Performance Engineering. Dynamic Climate Control.

The Smartwool Men’s Intraknit Thermal Merino Base Layer Crew is engineered specifically for high-exertion mountain activity where output levels fluctuate constantly. Harnessing advanced 3D-knit technology, this high-performance long sleeve seamlessly blends Merino wool with synthetic yarns—knitting targeted insulation directly over core zones while opening up breathable mesh structures across high-heat areas to dump heat the second your body starts working overtime.

• 3D-Knit Intraknit™ Technology: Seamless construction integrates warmth, breathability, and stretch directly into the garment, reducing weight and eliminating friction points under outerwear.

• Body-Mapped Mesh Ventilation: Seamless mesh structures knit into the back, underarms, and chest act as built-in heat dumps to instantly release moisture vapor before it turns into liquid sweat.

• Merino Performance Blend: Combines the natural thermoregulation, heat retention, and odor resistance of Merino wool with durable polyester and elastane for rapid drying and active 4-way stretch.

• Targeted Insulation Zones: Thicker knit structures insulate core areas to protect against icy ridge winds without adding bulk under your jacket.

• Seamless Elbow & Shoulder Articulation: Engineered ribbing around joint structures follows your body’s natural movements for zero pulling or binding while setting turns or carrying a pack.

• Performance Athletic Fit: Ergonomic second-skin silhouette keeps thermal materials flush against your skin to optimize moisture transfer and layer effortlessly under mid-layers and shells.