A socket comprising a body having an opening in which a contact-holder is housed, a cover articulated to the body and movable between a closed position in which it closes said opening and an open position in which it is raised from said opening, a yoke articulated to the body and movable between a lowered position and a raised position, the yoke having two arms which, in the lowered position, are intended to cooperate with a shoulder of a plug to retain the plug inserted into the socket, and a latch member articulated to the yoke and movable with respect to the yoke between a locked position and an unlocked position, the latch member having at least one pawl which, in the locked position, engages a corresponding seat of the body and which, in the unlocked position, is disengaged from said seat, and a cover-lock element articulated to the body and movable between an engaged position and a disengaged position, wherein the latch member has at least one cam portion that cooperates with the cover-lock element for moving the cover-lock element from the engaged position to the disengaged position when the latch member moves from the locked position to the unlocked position.