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 them, take the next size up from your normal shoe size. The booties have 100% Polyester filling for warmth, a cushioned heel, a 100% Nylon Shell, and a BLOCH rubber logo badge on the strap. They're not for outdoor wear.