birkenstock women's gizeh eva lightweight t-strap thong sandals black size 38 birkenstock the birkenstock gizeh is our classic thong sandal. modeled on the cork original, this sandal is made from ultra lightweight and highly flexible eva. these colorful sandals are shock-absorbent, waterproof, and skin-friendly. wear them at the beach, in the garden, or in wellness and spa areas. it's the perfect addition to your classic birkenstock sandals.