Continental's eco-friendly concept tire includes a renewable tread
 

Many efforts are underway to reduce the environmental impact of cars, but what about the tires those cars ride on? Continental thinks it might help. Roadshowreports the company has introduced the Conti GreenConcept (yes, a concept tire) where more than half of the materials are "traceable, renewable and recycled." You can even renew the natural rubber tread with little trouble — not a completely new idea, but refreshable treads have generally been reserved for large commercial trucks. Three renewals would be enough to ensure the material used for casing is cut in half relative to the total mileage.

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