Contact housing for an electrical plug connector

A contact housing for an electrical plug connector, having multiple contact chambers for receiving a respective contact body insertable through a placement opening into the contact chamber having, a respective elastically deflectable latching arm, protruding laterally into the contact chamber, for primary latching of the contact body inserted to its end position into the contact chamber, and having a respective locking element, displaceably guided transversely to the insertion direction of the contact body, that in its locked position protrudes, with a first locking projection, laterally into the contact chamber for secondary locking of the contact body latched in primary fashion therein. Provision is made that the locking element has a second locking projection that, in the locked position of the locking element, blocks the latching arm against deflection out of its position protruding into the contact chamber.