Stackable block with reduced height for a control unit

A stackable electric contact or signalling block comprising a casing that defines a volume of the block, the casing having upper and lower faces for connecting the block to another component, the casing accommodating the following elements:

• a screw for fixing the block to another component;
• and
• a press rod capable of moving from a rest position to an activation position for transferring a translation force to a component attached to the lower face of the casing, the press rod comprising an activation head in a form of a wedge capable of translationally engaging with a push-button or of rotationally engaging with a rotary knob;
• the casing comprising a guide cavity for guiding the press rod between the rest and activation positions of the press rod, in which guide cavity the press rod is accommodated, characterized by a device for guiding the press rod into the guide cavity comprising at least one guide tab accommodated in a matching guide slot passing through the activation head.