A side airbag module assembly for a vehicle seat back rest features a molded plastic cover with a Class A surface constituting the outside of the cover visible after installation in the backrest. By virtue of a key-driven actuator, multiple terminal strips are allowed to contact bus bars installed in more than one stage so as to produce multiple tones simultaneously. By means of the measuring system according to the invention, on the one hand, realistic conditions of a track system can be simulated and, on the other, a high metrological reproducibility of a load situation can be achieved. Molding procedure can be performed while the cooling medium is ejected from the ejection holes to a gap between the metal plate material and the mold. The lights are evenly spaced along the first wire.