Birkenstock Boston Oiled Leather Clog Sandal (Black, Size 45 EU) Birkenstock Unisex Boston Sandals are a veritable classic that can easily be worn all year round. Oiled nubuck leather upper Anatomically shaped cork-latex footbed One strap with an individually adjustable metal pin buckle Suede footbed lining EVA sole Birkenstock Unisex Boston Sandals have a legendary status thanks to its sophisticated, individual design. The upper is made from extra thick, oiled nubuck leather with an open-selvage finish. Deep heel cup The deep heel cup cradles the heel and keeps your natural cushioning right under the heel bone. Longitudinal arch support The longitudinal arch support runs along the sides of the footbed, providing stability with each step. Transverse arch support The transverse arch support runs through the middle of the footbed, helping ensure proper alignment and a solid stance. Raised toe bar The raised toe bar encourages the natural gripping motion of your feet, exercises the legs and stimulates circulation. More toe room A roomy toe box allows toes to move more naturally, promoting better balance and correct foot alignment.