Abstract: A modular unit for a modular signaling column has an outer element having an inner surface defining an inner space, a pair of apertures at axially opposite ends, a connection portion arranged adjacent to a first aperture of the pair of apertures and provided with first mechanical bayonet connections, and second mechanical bayonet connections arranged in the inner surface of the outer element suitable for cooperating with the first mechanical bayonet connections of an axially adjacent modular unit. The modular unit has an electrical connection plate having a plurality of arcuate or circular concentric contact tracks and a printed circuit board mountable in the inner space of the outer element. In a condition of mechanical bayonet coupling between two modular units the two modular units are electrically connected by sliding contact between a first connector of one modular unit and respective contact tracks of the other modular unit.