Intraknit Thermal Merino Base Layer 1/4 Zip – Men's

Built for high-output cold-weather activity, the Intraknit Thermal Merino 1/4 Zip is our pick for guys who run hot and need a base layer that keeps pace. Smartwool's 3D Intraknit construction zones insulation and mesh ventilation exactly where you need them, so you stay warm without overheating. The quarter zip gives you fast temperature control when the trail kicks up.

• Merino wool blend manages moisture and resists odor naturally — no synthetic funk after a long day out
• 3D Intraknit construction places insulation and mesh ventilation zones in a single seamless knit — no seam bulk, no pressure points
• Slim fit layers cleanly under a mid or shell without bunching or riding up during movement
• Quarter-zip collar lets you vent fast on climbs and seal back up when you stop — one hand, five seconds
• Available in Winter Moss, Twilight Blue, Charcoal-Nightfall Blue, Eggplant-Black, and Black-White across sizes S–XXL