BUILT IN ORTHOTIC ONLY OR ORTHOTIC MADE SEPARATELY. Classic two-strap style in a variety of materials with fully adjustable straps and shock-absorbing EVA sole. Product Details - Upper material: Nubuck - Quality leather is buffed for a soft and velvety finish. Footbed: The original Birkenstock footbed - Featuring pronounced arch support, deep heel cup, and roomy toe box. Footbed molds and shapes to your foot. Sole material: EVA - Flexible, lightweight, durable and shock absorbing.