I could never find socks with grippy soles bigger than toddler sizes in stores, so I tried these. My 5 yo is growing out of 5T socks but I don't trust him with regular socks when he runs around like crazy on our tile floors!  Fortunately these socks work great  they fit well, he doesnt complain about feeling the grippy bumps through the socks like some other brands weve tried, and they seem to be a good quality thick material. Note that when buying these, you select the SOCK size, which is not the same as SHOE size. I googled a sock size conversion chart and the size I ordered fit perfectly.