- The new style of Birkenstock thick-soled buckle shoes adds a new flavor to street style. The exaggerated PU sole can be worn all day long. The nubuck leather is soft to the touch, hinting at the inner comfort. On the inside, a deep silhouette The dark blue insole maximizes your comfort to match your daily commute! Upper: suede, lining: sheepskin, sole: cork midsole and EVA rubber molded bottom, size: 35-40,