What makes an OluKai sandal truly built to last We like to think it's a few things: tradition, craftsmanship, and attention to detail. The Hiapo is constructed with naturally tumbled or marbled full-grain leather using hand-sewn traditional whipstitching, complete with Polynesian tattoo artwork details on the footbed. One of our original sandals (hence, its namesake), Hiapo only gets better with age. Made for the beach, not the ocean-prolonged contact with water may cause damage.