Upper material: Birkibuc - a synthetic material made of acrylic and polyamide felt fibers that is comfortable and tear-resistant. This material offers a textured finish that looks and feels like velvety nubuck. Wipes clean with mild soap and water. Footbed: The classic Birkenstock footbed - features pronounced arch support, a deep heel cup, and a roomy toe box. The footbed conforms to the shape of your foot. Sole material: EVA - flexible, lightweight, durable and shock absorbing.