The BIRKENSTOCK Boston is a timeless classic with its distinctive and individual style. This special edition is made of EVA, a synthetic material that is both waterproof and lightweight making it perfect for wearing all year round. The anatomically shaped BIRKENSTOCK footbed and upper/lining/sole are crafted from a single piece of EVA material, so you can enjoy this lightweight sandal after the gym or at the beach. Plus it's waterproof, washable, and made in Germany.