The connection board is connected in-between the main unit and the voice station with two RJ45 connectors. The SLB-IF1's screw terminal has the same connections as the screw terminals on some of the SL6 voice stations, making SLB-IF1 suitable for installations where there is not enough room for a screw terminal on the voice station.

By changing the jumper on the board it is possible to change the polarity of the external pictogram relays to + or -.

SLB-IF1 can be mounted using double side tape or on a DIN rail.