The upper of this unisex two-strap sandal can be individually adjusted to the wearer’s feet using two sturdy metal buckles – guaranteeing a good fit and firm support. Every pair of Birkenstocks is made from the highest quality materials. Birko-Flor Upper / Classic Footbed - Suede Lined Birko-Flor is the Birkenstock trade marked synthetic leather. It is a skin friendly, easy care fabric. Clean with a damp cloth.