I am selling a set of 5 school socks that are designed to hide dirt. The size is 22-25cm, and they appear to be made in Japan. Please check the 4th photo for the material composition. I originally purchased two sets of 4, but I only used 3 pairs, so I am selling the remaining 5 socks. Although they are unused, they have been opened, so there may be some dust or dirt. Please understand that these are used items before considering a purchase. Shipping will be via Nekopos.