Abstract: The invention concerns an insert designed to be mounted in a calibrated hole (2) of an element (1) for fixing and electrically contacting an electrically connecting socket, consisting of an electrically conductive ring (3) having a sleeve (3a) which is secured to a saddle (3b) and of a screw (4) which is provided with a shaft (4a) designed to be inserted into the ring (3) and with a head (4b) facilitating its being screwed and enabling further the socket to be clamped (5), between itself and the saddle (3b) of the ring whereof the sleeve (3a) has been previously inserted into said hole (2) of the element (1).