A communication module for a communication or automation device includes a housing having a connection region that can be brought into contact with a base module of the communication or automation device, wherein centering pins of the connection region are insertable into corresponding receptacles in the base module, a fastening screw having a threaded section penetrates the housing between the centering pins, where the threaded section of the fastening screw is screwable into a threaded hole in the base module, and a passage for receiving the fastening screw is arranged substantially centrally in the housing and extends at right angles to the connection region, the fastening screw has a driver ring connected to it that surrounds a section of a shaft of the fastening screw and where, along the passage, a cutout is provided in the housing for the driver ring that is axially displaceable inside the cutout.