evo.com | Smartwool Long Underwear Tops > The Smartwool Classic Thermal Merino Base Layer 1/4 Zip Top isn't just a baselayer, it's a stink-resistant lightweight champ, made for getting after it in the cold. Layer with ease thanks to this slim-fitting garment that features a 1/4 zipper and 100% breathable merino wool. Make sweating fun with the Smartwool Classic Thermal Merino Base Layer 1/4 Zip Top. 100% Merino Wool Made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance. Raglan Sleeves Zipper Length 10" (25 cm) Flatlock Seam Construction Designed to Eliminate Chafing Slim Fit Slim fit is intended to follow the contours of the body | Smartwool Classic Thermal Base Layer 1/4 Zip Top Men's 2026 - Large Gray