Back-strap sandal in a variety of materials with fully adjustable straps and shock-absorbing EVA sole. Features Birkenstock's classic suede-lined cork/latex footbed. Product Upper material:Â Oiled Leather - Thick yet supple leathers without additional dyes to keep the leather breathable, durable and comfortable. Footbed:Â The original Birkenstock footbed - Featuring pronounced arch support, deep heel cup, and roomy toe box. Footbed molds and shapes to your foot.Sole material:Â EVA - Flexible, lightweight, durable and shock absorbing.