ROTOTO 1618 Retro Winter Room Socks in TerracottaROTOTO 1618 Retro Winter Room Socks. A wool blend winter sock from Rototo. Classically designed and traditionally constructed in Japan using old school knitting machines. 50% wool, 30% acrylic, 10% nylon, 7% polyester, 3% polyurethane Machine Wash Avoid Tumble Drying, as it may cause shrinkage. Made in Japan ROTOTO Crafted and designed in Japan, RoToTo uses traditional and modern manufacturing techniques, to create the ultimate cool comfort sock with