The Karmel uppers and the removable footbed are made from over 50% I'm Green Biobased injected EVA, making it lightweight and durable, and easy to clean. The footbed is cushioned and featuresDansko Natural Arch technologyfor added arch support, and the channeled outsole provides durability and long-lasting wear. This is a rain boot that feels great and is made from materials you can feel good about. Easy clean uppers. Waterproof construction and lightweight. I'm green bio-based EVA (over 50%) which is lightweight and durable. Removable, energy return EVA footbed with Dansko Natural Archtechnology for added support. Textile footbed cover treated withAegis Microbe Shield odor control. Strategically placed lightweight rubber outsole pads for durability.