37.5% Merino, 37.5% Acrylic, 15% Nylon, 10% EA. Lycra Imported MERINO WOOL wicks away moisture to keep your feet dry and provides a soft feel against the skin. EA. LYCRA all throughout the sock means no slipping or bunching up. MEDIUM CUSHIONING on the shin for protection from the inner boot. MESH INSTEP minimizes bulk on the top of the foot and promotes heat and moisture release with advanced ventilation.