Birkenstocks Siena Big Buckle Natural Leather Oiled Sandals Dusty Blue 41 10 The BIRKENSTOCK Siena boasts a refined appearance. Crossed straps give the sandal its unique and special look. The Big Buckle version features a large, elegant pin buckle – a fantastic, striking eye-catcher on this otherwise understated sandal. The lining of the semi-exquisite footbed is covered with soft smooth leather and matches the shoe in color. The upper is made from extra thick, oiled nubuck leather with an open-selvage finish. Narrow width. In excellent condition with very light signs of wear. Please see all photos for more details. Size 41 / women's 10