The invention relates to a connector comprising at least one first connector part and at least one second connector part. The connector parts can be connected to one another in a fluid-tight manner and can be locked to one another via at least one closure element. One of the connector parts has at least one openable seal element which blocks a flow in the closed state, in particular a septum or a seal disk, and the other connector part has at least one opening element for opening the seal element. One of the connector parts has at least one protrusion, and the other connector part has at least one receiving area, the opening element and the seal element being arranged relative to each other such that the opening element opens the seal element only when the protrusion is inserted into the receiving area.
