Zurich Tech Black Suede Leather Classic Adults often in a contrasting material often in a contrasting material offers optimum grip in a seamless silhouette The Birkenstock Cotton Sole Invisible socks are certified cotton sneaker socks with the original Birkenstock footbed comfort sole Birkenstock brings the classic Zurich model into the 21st century by embellishing the soft suede upper with a juxtaposed technical fastener This element on the Birkenstock Zurich Tech brings a little ingenuity from the slopes of the alps and takes it into a futuristic feel without compromising the combination of stability and lightness of the popular sandal