The invention relates to an insulating body of a plug-in connector, said body consisting of a plug-in part (10), in which contact elements (11) are located, and of a connecting part (20) which in turn has connecting elements (21) that can be electrically connected to conductor tracks of a printed circuit board and/or to individual conductors of a multi-core cable that is to be connected. The plug-in part (10) and the connecting part (20) can be interconnected, thus allowing the contact elements (11) to make electric contact with the connecting elements (21) of the connecting part (20).