These warm-up booties are perfect for dancers. Ideal for use between classes and rehearsals. They are filled with 100% Polyester for warmth and comfort, have a cushioned heel, and a 100% Nylon Shell. The sizing options are XS (US 13.5-1.5), S (US 4-6), M (US 6-8), L (US 8-10), XL (US 10-12). Not for outdoor use.