Made from mid-weight Merino wool, the Darn Tough Vermont Function X OTC Midweight w/ Cushion Padded Shin socks provide maximum comfort and warmth for resort skiers and riders. Their Terry cushioning in the shin and the 'X' on top of the foot provide 57% Merino wool, 40% nylon, 3% Lycra spandex. Machine wash in warm water on gentle cycle with socks inside-out. Do not bleach. Tumble dry on low or hang dry. Do not dry clean. Made in the USA.