Spring skiing or summer camping? The year-round Merino 150 Base Layer Long Sleeve is game for either. With Smartwool&';s Core Spun technology, they&';ve wrapped lightweight Merino around a nylon core for added durability, while still keeping the comfort of ultra-soft, responsibly-sourced Merino next to skin. They also added smooth flatlock seams to help minimize chafing and offset shoulder and side seams to lie smoothly beneath pack straps. Select colorways feature a more responsible plant-based-dye technique. No matter the season or the activity, this base layer is made for it. Features Slim Fit Smartwool&';s lightest weight Merino jersey fabric uses a nylon core to increase durability while still keeping 100% Merino wool next to skin Offset shoulder and side seams designed to increase comfort and minimize chafing while wearing a backpack Side seams wrap to front for body-enhancing fit Flatlock seam construction designed to minimize chafing Light Woodsmoke, Indigo Blue and Black Marble Wash colorways feature plant-based dye technique Knit in China: 87% Merino Wool, 13% Nylon. Exclusive Of Decoration Style: SW000748