A remotely configurable wireless intercom system and method for an establishment having a staff. The pivotable handle part engages through a slit of the main part and is linked to a slider. A raised sealing rim extends at least partially around the central portion. The size of these zones is related to the aperture of the projection lenses, the magnification produced by the Fresnel, and the optical properties and position of the image corrector plate. Therefore, messages are transferred faster and media independent handover is performed more quickly.