A method for manufacturing a joining connection between a luminously efficacious part and a metal component of a lighting device of a vehicle. A microstructure is generated in a joining surface of the metal component, the microstructure having undercuts with respect to the joining surface. The plastic material of the plastic part is softened in an area of the complementary joining surface near the surface with the aid of an introduction of heat. The plastic part and the metal component are pressed together with a pressure force in such a way that a portion of the softened plastic material penetrates the undercuts of the microstructure. The plastic material of the plastic part is cooled thereby forming a new strength of the softened plastic material of the plastic part.

A method for manufacturing a joining connection between a structural part and a metal component of a lighting device of a vehicle, the method comprising at least the following steps: Generating a microstructure in a joining surface of the metal component, the microstructure having undercuts with respect to the joining surface; Softening the plastic material of the plastic part in an area of the complementary joining surface near the surface with the aid of an introduction of heat; Pressing the plastic part and the metal component together with a pressure force in such a way that a portion of the softened plastic material penetrates the undercuts of the microstructure; and Cooling the plastic material of the plastic part, forming a new strength of the softened plastic material of the plastic part.

A multi-layer exercise mat including a first layer including an outer surface and an opposing inner surface, the opposing inner surface of the first layer including a first array of three-dimensional features integral with the first layer; and a second layer including an outer surface and an opposing inner surface, the opposing inner surface of the second layer including a second array of three-dimensional features integral with the second layer. The first and second arrays of three-dimensional features are configured to grip each other to removably secure the inner surface of the first layer to the inner surface of the second layer.

A multi-layer exercise mat including a first layer including an outer surface and an opposing inner surface, the opposing inner surface of the first layer including a first array of three-dimensional features integral with the first layer; and a second layer including an outer surface and an opposing inner surface, the opposing inner surface of the second layer including a second array of three-dimensional features integral with the second layer. The first and second arrays of three-dimensional features are configured to grip each other to removably secure the inner surface of the first layer to the inner surface of the second layer.