An electro-optical module comprising flexible connection cable and aligning capabilities is disclosed. Electro-optical devices may be soldered on a transparent substrate such as glass or a substrate comprising an optical waveguide wherein electrically conductive traces are designed, forming an electro-optical module. When such electro-optical module is inserted and aligned into a printed circuit board, the external part of the substrate, comprising electrically conductive traces and pads, referred to as flex-cable, is bent down toward the mounting plane of the PCB allowing to establish electrical connections between these pads and the PCB. The substrate may be broken along a pre-formed groove, and the external part of the substrate can be removed leaving the flex-cable section in place.