A locking element for detachably fixing a fluid-carrying plug to a connector, including, a locking element having at least one spring element, by means of which the locking element is moved automatically into a locking position with the connector as the plug is inserted, and held in its locking position, wherein the locking element has a limb that is moved at right angles to an axis of the connector, in which limb there is formed a bore for the plug to be led through; and characterized in that the locking element consists of a spring steel and the spring element is formed in one piece therewith.