ColdPruf Men's Classic Base Layer Long Sleeve Crew Neck Top 100% Merino Wool Imported Soft, lightweight 100% Merino wool in a single layer jersey knit able to move with wearer's body and stretch while maintaining its shape Modified raglan yoke design offers seamless shoulders Drop tail maintains coverage in various activities Tagless labeling and flat seems provide a smooth fit and extra comfort Naturally occurring moisture management wicks perspiration and dries quickly Perfect as a base layer or on its own. Best used for layering in cold to very cold weather and medium to high activity levels