Abstract: This invention relates to a rubber plate (elastic) (FIG.1) which, when soldered at its edges (FIG. 1A) to the inside of the body (case) of a watch (or other object) (FIG. 3A), totally seals it against water and dust. At the same time, in view of the fact that it is soldered at its sides (edges), its central part remains totally free, thus permitting the movement of the outside control buttons (FIG. 4C, D and 6A) and activating the mechanism, whether it is electronic (FIG. 3D) or mechanical (FIG. 5 and 7) (digital or analog). When the external controls are pressed, the corresponding function is switched on internally (FIG. 4E, F). A single plate (FIG. 3A) can be used for various controls (FIG. 3B, C) or one plate for each control (FIG. 4A, B), depending on the distance between them and the space available in the watch-case.