Abstract: A round plug connector for releasably connecting lines has at least one housing element for receiving at least one insulating body and at least one locking element for releasably connecting to a mating plug connector. The housing element receives at least one circumferential spring element, and the spring element is made of an electrically conductive material in order to attach to an electromagnetic shielding, wherein the spring element is held in a circumferential recess of the housing element and has at least two bulges facing radially outwards.

Abstract: A plug-in connector element with a locking device (14) for releasably locking on a plug partner (12), wherein the locking device has a plurality of locking hooks (16, 18) which are distributed on the circumference of a main body (10) and which are detented at a front end in the plug-in direction and are pivotable in a radial direction between a locking position and a release position, characterized in that the locking hooks (16, 18) are designed as structural parts which are separated from each other and from the main body (10) and which are mounted on the main body such that they are each tiltable about an axis running at right angles to the insertion direction and at right angles to the radial direction, and which, at the end opposite the detent, are each supported resiliently on the main body in the axial direction.

Abstract: A printed circuit board plug-in connector is provided comprising a connector installation housing, an insulating body and a shielding connection element, for the shielding connection of a plug-in connector installation housing to a printed circuit board. The shielding connection element is flat or has at least one flat deformation section which is arranged, in the plug-in direction, in a through-slit of an insulating body mounted on the printed circuit board, and protrudes out of the insulating body with two contact regions in order to electrically contact the metal plug-in connector installation housing.

Abstract: A printed circuit board plug-in connector is provided comprising a connector installation housing, an insulating body and a shielding connection element, for the shielding connection of a plug-in connector installation housing to a printed circuit board. The shielding connection element is flat or has at least one flat deformation section which is arranged, in the plug-in direction, in a through-slit of an insulating body mounted on the printed circuit board, and protrudes out of the insulating body with two contact regions in order to electrically contact the metal plug-in connector installation housing.