These are children's tabi socks. They were used once by a child for a tea ceremony experience, for about an hour, and have been stored at home since then. The exact size isn't written on the tabi themselves, but measured with a ruler, it's about 18.5 cm. The name was written on the heel, so it has been erased with a marker. There is a slight stain on the soles as shown in the photos, but they are relatively clean and I think they can still be used.