Classic Thermal Merino Base Layer Bottom Boxed

Cold mornings, long days, zero excuses.

The Smartwool Classic Thermal Merino Base Layer Bottom (Men’s) delivers dependable warmth without bulk, thanks to 100% Merino wool and a soft interlock knit that traps heat while letting moisture escape. You stay warm, dry, and comfortable — even when the pace picks up.

The updated fit moves naturally with your body. Flatlock seams reduce rubbing. A Merino-lined elastic waistband and functional fly keep things practical and comfortable from first chair to last lap.

Built for skiing, winter hiking, cold-weather running, travel — and any day when the thermometer says “don’t bother,” but you go anyway.

Key Features

• 100% Merino wool next to skin — warm, breathable, and odour-resistant
• Interlock knit for soft, durable comfort
• Slim fit sits close to the body for efficient layering
• Flatlock seams help reduce friction and chafing
• Merino-lined elastic waistband for added comfort
• Functional fly for everyday usability
• Warmest-weight Merino for serious cold

Specs

• Fabric: 100% Merino Wool (exclusive of decoration)
• Fit: Slim
• Inseam (M): 30 in / 76 cm
• Construction: Interlock knit
• Seams: Flatlock
• Model: SW016362
• Made in: Vietnam