Arrangement comprising an electrical conductor track carrier and a device applied on the conductor track carrier, - wherein the device is a fibre-optoelectronic device and comprises: a housing , at least one electro-optical or optoelectronic component , at least one fibre-optic interface connected to the electro-optical or optoelectronic component, and at least one electrical interface for connecting the device on the conductor track carrier, and - wherein the electrical interface comprises at least one bent electrical soldering connection element which extends laterally outwards and is soldered on the conductor track carrier laterally outside the outer housing contour , - wherein the at least one bent electrical soldering connection element is fitted by one end thereof to a base connection section of the housing base of the housing and extends outwards from there laterally in such a way that the other end of the soldering connection element - in plan view - protrudes laterally and is soldered on the conductor track carrier laterally outside the outer housing contour , and - wherein the soldering connection element is bent away from the base connection section in such a way that the base connection section, and thus the housing base , is at a distance (A) from the conductor track carrier that creates mechanical play, characterized in that - a reflection-reducing characteristic impedance matching element is present in at least one partial section of the gap between the base connection section and the conductor track carrier, - the housing base has a base bearing section , which bears directly on the conductor track carrier, and - the housing has at least one securing section which is screwed to the conductor track carrier. - wherein the device is a fibre-optoelectronic device and comprises: a housing , at least one electro-optical or optoelectronic component , at least one fibre-optic interface connected to the electro-optical or optoelectronic component, and at least one electrical interface for connecting the device on the conductor track carrier, and - wherein the electrical interface comprises at least one bent electrical soldering connection element which extends laterally outwards and is soldered on the conductor track carrier laterally outside the outer housing contour , - wherein the at least one bent electrical soldering connection element is fitted by one end thereof to a base connection section of the housing base of the housing and extends outwards from there laterally in such a way that the other end of the soldering connection element - in plan view - protrudes laterally and is soldered on the conductor track carrier laterally outside the outer housing contour , and - wherein the soldering connection element is bent away from the base connection section in such a way that the base connection section, and thus the housing base , is at a distance (A) from the conductor track carrier that creates mechanical play, - a reflection-reducing characteristic impedance matching element is present in at least one partial section of the gap between the base connection section and the conductor track carrier, - the housing base has a base bearing section , which bears directly on the conductor track carrier, and - the housing has at least one securing section which is screwed to the conductor track carrier. <EOS>