The ideal trekking sock. The Teko M3RINO.XC wool wicks moisture and is naturally anti-microbial. Great for cold weather activities walking, hiking and trekking in boots. Our unique Achilles Wrap System design combined with anatomical Y-heel delivers superior comfort and performance. Heavy merino cushioning surrounds the foot and the lower calf in this sock. Our merino wool is from South America. The wool is shrink resistant.