I am selling a set of four mezzo piano socks. The size of each is 20-22cm. Please check photos 4, 7, 10, and 13 for the material. The color of the socks in the second photo is black. Although they are unopened, they have been stored at home, so I am selling them as used items. Please consider this before purchasing. Shipping will be via Nekopos. Thank you very much.