Socks Size Size S: 6-9 years/5.5-7.1in(14-18cm) Size M: 9-12 years old/7.1-8.7in(18-22cm) Our sports socks are specially designed for 6-12 years old children, please choose the right size according to your child's foot length. Kids Non-Slip Soccer Socks Our children's grip socks are made of high quality cotton and nylon fabrics, thick, soft, comfortable, non-slip and breathable. Kid's Socks for Multiple Occasions These non-slip sports socks are not only suitable for soccer, basketball, running and other sports, but also for all kinds of outdoor activities, fitness, or as floor socks and warm socks at home.