The Birkenstock Women's Gizeh Essentials EVA Sandals - Narrow are designed with your comfort in mind. Modeled from the cork Gizeh's, these thongs are made from super-light and highly flexible, odor-neutral EVA (ethylene vinyl acetate) that has been tested for harmful substances and offers numerous positive attributes. They are highly elasticated, shock-absorbent, waterproof, and skin-friendly--and offer the comfort you have come to expect from Birkenstock.