Abstract: A telephone instrument is designed in the shape of an angle, whereby the upper side has a steeper inclination towards the user. The rear wall is at approximately a right angle to the upper side. The bottom side runs at a specific distance, parallel to the upper side and to the rear wall. Since the distance between the upper side and the bottom side is not very great, i.e. since a maximum of only two printed circuit boards can be accommodated one on top of the other in this space, the bottom side below the upper side has a trough which serves both to accommodate an additional printed circuit board and to provide cable entries. This trough does not extend over the total width of the telephone instrument but is narrower. In order to expand the keyboard, one part of the upper side can be moved in the longitudinal direction, away from the user, so that an additional keyboard or indicator device below it is made available.