Birkenstock Kids' Mayari Birko-Flor Sandal (Toddler/Little Kid)Size Chart The Mayari for kids from BIRKENSTOCK a comfortable sandal with adjustable, crisscrossing straps that form a single loop around the toe. Classic support and adjustability, designed beautifully. The upper is made from the skin friendly, hard wearing synthetic material Birko Flor. Anatomically shaped cork latex footbed Upper: Birko Flor Footbed lining: suede Sole: EVA Details: two straps, each with an individually adjustable metal pin buckle;