The invention relates to a plug connector, in particular a direct plug connector, for contacting contact openings of a circuit board, the plug connector including a contact carrier which can include coding devices, in particular coding pins and a polarity reversal safety, in particular configured as polarity protrusions; conductor insertion channels formed by the contact carrier and configured to receive connection conductors, and contact recesses configured to receive plug contacts; a primary safety that supports the contact carrier at the circuit board and that is in particular configured as interlocking elements, characterized in that the primary safety includes at least two interlocking arms that are arranged in pairs adjacent to each other wherein interlocking devices of the interlocking arms have different interlocking geometries.