EUC Women’s Birkenstock Boston Essentials Eva •smoke-free, pet-free home •worn a handful of times •size 7-7.5 medium Our best-selling clog in an ultra-lightweight style. The Boston EVA is made from water-friendly material, giving you a flexible design built on the contoured footbed you love most. The perfect pair for pre-workout, post-practice and all the rest days in between.