The Birkenstock Yao Birkoflor is an asymmetric eye-catcher which will turn heads. The upper is made of Birko-Flor® in a sophisticated nubuck look and features a soft, breathable layer of fleece. This hard-wearing synthetic material is skin-friendly. It includes anatomically shaped cork-latex footbed, flexible leather lining, and EVA outsole. It also includes two straps, each with an individually adjustable metal tongue buckle.