Gr&ouml;do (Groedo) Organic Wool Cotton Children Kids Socks (3-pack) Made in Germany Machine washable 85 F degrees (30 C degrees) 75% virgin wool (the wool one gets from shearing a lamb for the first time), 23% organic cotton, 2% elasthane Certified by GOTS (global organic textile standard) Made in Germany Size 1-2 years US shoe size 3 1/2 - 6 (foot length 4 3/8 - 5 1/8") . Size 3-4 years US shoe size 6 1/2 - 9 (foot length 5 3/8 - 6 1/4"). Size 5-6 years US shoe size 10 - 12 (foot length 6 1/2 - 7 1/4"). Size 7-8 years US shoe size 13 - 2 Y (foot length 7 1/2 - 8 1/4"). Size 9-10 years US shoe size 3 Y- 5 Y (foot length 8 1/2 - 9").