Memoi girls cotton knee socks are model MK-5056. The size is stitched into the bottom of the sock to make for easy sorting. The light gray option is a heather color.  The light denim looks a little lighter than the photo shows. These Memoi knee socks are good quality, soft, and have a comfortable top band.  80% Cotton, 17% Nylon, and 3% Spandex.