the company emblem 51 is three dimensional and has penetrations 54 in the relief between the lettering and the image the penetrations 54 are closed at the backside by the expandable membrane 52 and are thus sealed the grip plate 53 positioned underneath is seated on the free ends of the levers 47 and has a hole 55 at a defined location the three layers 51 52 53 of the attachment 50 are fixedly connected to one another at their periphery 24 at the central area of the attachment 50 a sufficient spacing is provided between the grip plate 53 and the flexible layers 51 52 positioned above normally the contact position 50 1 which is indicated in fig5 by an auxiliary line 50 1 is present where the modular unit 21 is positioned closely at the inner layer 37 within the cutout 32 of the outer skin 40 in this case the central dome 38 of the elastic inner layer 37 projects through the hole 55 of the grip plate and as illustrated in fig5 is aligned with a yielding location 23 of the company emblem 51 the yielding action is recognizable for the pressure actuation 20 illustrated in fig6 in the company emblem 51 the yielding location 23 is transferred into the pushed in position 23 u2032 illustrated therein where the dome of the elastic inner layer 37 positioned behind has been pushed into the area of the grip plate hole 55 and thus has suffered a flattening 38 u2032 accordingly the contact maker.