Named with the planet in mind, SmartWool's Saturnsphere socks combine softness and a cushioned sole. . SmartWool's merino wool fibers are longer than other conventional wool-sock fibers, creating a knitted yarn that is itch free and silky soft. Smooth toe seam, supportive arch brace, cushioned sole. Machine wash and dry with no shrinkage. 90% merino wool, 8% nylon, 2% spandex. Machine wash and dry with no shrinkage.