Abstract: Extruded rubber profiles are often prone to a warping and a distortion during their production. In order to achieve in windshield wiper blades rubber profiles a corresponding stiffening and at the same time a simple means of mounting a spring elastic supporting strip is embedded into the heel of the rubber profile by means of injecting rubber mass partly around the supporting strip. The corresponding shaping of an extrusion head including an extrusion die allows a leaving of rubberless areas extending along the two longitudinal edges of the supporting strip.