Smartwool's Men's Merino 250 Base Layer Colorblock Crew features 100% responsibly sourced Merino wool made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance. With shoulder panels and a flatlock seam construction, this base layer brings consistent comfort, as well as reliable warmth and durability, to winter hiking, running, and skiing. Slim Fit 100% Merino wool fabric made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance Shoulder panels eliminate top shoulder seams Flatlock seam construction designed to minimize chafing Knit in Vietnam: 100% Merino Wool. Exclusive Of Decoration Garment weight: 280 g = 9.88 oz