Use these warm - up booties between dance classes and rehearsals. They are designed for adult dancers. Sizing information: XS fits US 13.5 - 1.5, S fits US 4 - 6, M fits US 6 - 8, L fits US 8 - 10, XL fits US 10 - 12. If you plan to wear pointe shoes with the booties, take the next size up from your normal shoe size.