Fit & Design: Fits US kids' shoe sizes 9T-3 Stay-Up Technology: the perfect tension and elasticity to keep them exactly where you want them Cushioned footbed Extra-Long Staple Cotton: a premium fiber that's soft, durable, and smooth against your skin - it shrinks minimally in the wash and will hold up wear after wear Seamless toe A Y-Stitched Heel creates a natural cup around your heel made to fit your feet Their Honeycomb Support System cradles the arch of your foot, like a firm but comfortable hug around your midfoot