Thunders Love Wool Shetland Grey Socks are made with a 100% shetland grey yarn. As we didn't use any elastic fiber in it construction they are ribbed knitted to improve the adjust. Shetland wool is high quality knitting yarn, it comes from the Shetland Sheep, friendly and beautiful sheeps with a soft wool, this yarn usually it used without any dye, but we decided in this case dye it in grey color.