Borrowing a page from the car industry, Adidas Futurecraft Biofabric Shoes aren't an actual product, but instead a concept that offers a glimpse of the future. As the name suggests, its upper is made from 100% Biosteel fiber, a nature-based fiber meant to mimic natural silk. The material is lighter than traditional synthetic fibers and is one of the strongest fully natural materials in existence. Thanks to its natural origins, it also allows the shoes to be 100% biodegradable, making these some of the most eco-friendly athletic shoes ever made.