摘要 |
<p>The unit has a circular base body (3) manufactured from an elastic material, rubber foam-like material e.g. polyurethane-foam and rubber-like material e.g. solid rubber, and designed in a discoidal manner. The circular base body is provided with a circular opening (4) and a pressable surface, where the circular base body is provided with a groove (5) that extends over a partial area of the height of the base body.</p> |