The new authentic Birkenstock Boston casual sandals in khaki feature a narrow EU shoe size and a UK size of 10.5. These slip-on sandals have a buckle closure, making them perfect for casual occasions. The EVA outsole provides comfort and durability, while the cork insole offers added comfort. The faux leather upper material and buckle feature make these unisex sandals a stylish and versatile choice for the spring, summer, and autumn seasons.