From Vionic, the Opal leather mules feature: Premium leather upper Slip on styling Built-in VIO MOTION Technology footbed featuring contoured arch support, and a deep heel cup to provide stability & forefoot flexibility  Lightweight, flexible EVA midsole helps reduce stress on feet, ankles and knees Durable TPU outsole  Approx. 0.75" platform height Approx. 1.125" heel height It's recommended to wear your new pair for a few hours to allow your feet to adapt to the new support Imported.