The invention deals with the design for a mating surface for axes, shafts and flanges. The connecting element is characterized by semi-circular, parallel running slots and webs. These characteristics lead to a cost-effective manufacturing. The geometric principle of the invention is based on semicircles with different epicenters in order to make use of the whole front face. The Schürmann-mating surface element competes against the Hirth-mating surface element. The invention is of equal value but it represents an explicitly cost-effective alternative. It features space-saving more effective uses compared to a simple slot and key joint.