Sizing:
Infant: 0-3 Toddler Shoe Size
Extra Small: 4-6 Toddler Shoe Size
Small: 7-10 Toddler Shoe Size
Medium: 10-13 Toddler/Kids Shoe Size
Large: 1-7 Big Kids/Womens 4-10/Mens 4-8 Shoe Size

Sizes Infant, Extra Small, Small Medium have "Trick" on one foot "Treat" grips on the opposite foot and size Large has a stitched "Trick" and "Treat".