Kwekoo Men's Wool Acrylic Winter Outdoor Hiking Boot Work Socks 2 Pair Pack 30% Wool, 35% Acrylic, 33% Polyester, 2% Spandex Machine wash cold with like color. Only non-chlorine bleach when needed. Tumble dry low heat. Striped with Contrast Heel and Toe. True Ribbed quality socks. Very soft hand feel. Smooth toe seaming. Made from recycled wool and acrylic yarns. Naturally moisture wicking because of wool. Not sure yet. No worries 100% Money back guarantee.