The new Michelin Protek Max tube repairs tyre damage caused by punctures all by itself. Specially shaped rubber curvatures on the tread flank, when inflated in order to form a rubber reserve and reduce the surface tension of the tube. If a nail or pointed object pierces the tube, the "excess" rubber from the curvature closes the hole. At the same time, a special gel from within inside the tube flows over the punctured area and seals it permanently.