The Erin is made from genuine Twinface sheepskin with the craftsmanship you expect from UGG® Australia. A simple hook and loop closure, offers on and off easily and comfortably. The Infant UGG® Erin is made from genuine Twinface sheepskin with the craftsmanship you expect from UGG® Australia. A simple Velcro closure, offers on and off easily and comfortably. S = 2-3 M = 4-5 L = 6-7