Birkenstock Boston EVA Mules In Black. Regular Fit. EVA textured uppers with a strap across the foot featuring adjustable Birkenstock branded buckle fastening. A contoured footbed and a textured EVA undersole with the signature Birkenstock logo debossed on the instep. Please note to go by the EU sizes: 41 - 7 42 - 8 43 - 9 44 - 10 and 45 - 11. Colour: black