Elizabeth Renstrom for TIME
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Cornelius Schmitt, CEO and co-founder of Zellerfeld, has grand ambitions: to put fully recyclable 3D-printed shoes “on every foot in the world.” The startup currently uses 200 3D printers of its own design to create custom-­fitted shoes based on smartphone scans of the buyer’s feet. Each piece of futuristic footwear is made entirely of a single material, thermoplastic polyurethane, eliminating the sorting headaches that prevent mixed-­material items from being recycled. At the end of their life—or the end of a season—the shoes can be sent back to Zellerfeld and turned into new designs. The company has worked with designers from Kanye West to Moncler on a range of sneakers and sandals, with more high-profile collaborations on the horizon.

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