The BIRKENSTOCK Boston model is a true classic that can be worn all year round. With its refined, individually adjustable design, the Boston has long been a legend. This mule, which, once worn, evokes the lightness of cork sandals, is made of particularly lightweight and flexible EVA plastic. The high-quality EVA plastic, odorless and free of harmful substances, combines many positive features: it is very light, extremely elastic, cushioning, water-resistant, and skin-friendly.