We've updated the fit of our Men's Classic Thermal Merino Base Layer 1/4 Zip to improve functionality while also enhancing aesthetics. As one of our heaviest base layer tops and best base layers for cold weather, this garment uses 100% responsibly sourced Merino wool, shoulder panels, and a flatlock seam construction to help minimize chafing as well as help keep you comfortable and temperature-regulated as you enjoy high-intensity skiing, hiking, running, and more. Fit & Design: Slim fit is intended to follow the contours of the body Center-front zipper Interlock knit for comfort Flatlock seam construction and offset shoulder and side seams designed to help increase comfort and minimize chafing Side seams wrap to front Technology: Moisture management Odor-resistance Additional Details: Size medium center-front zipper: 10"" (25 cm) Machine Wash Warm Gentle Cycle Wash With Like Colors Do Not Bleach Tumble Dry Low Cool Iron As Needed Do Not Iron Decoration Do Not Dry Clean