Shielded circular plug-in connector

A circular plug-in connector for establishing a shielded plug-in connection to a mating plug-in connector, comprising:

• a contact carrier having at least one electrical contact element;
• a shielding sleeve that surrounds the contact carrier at least in part;
• and
• a screw housing that is rotatably connected to the shielding sleeve and configured to screw the circular plug-in connector to the mating plug-in connector,
• wherein a connection portion of the shielding sleeve is received in a receiving space of the screw housing,
• wherein the circular plug-in connector is configured such that there is shielded contact between the screw housing and the shielding sleeve,
• wherein the shielding sleeve comprises a collar in the connection portion, and
• wherein the circular plug-in connector further comprises a stopper configured to close a receiving opening of the receiving space at least in part, such that the collar is trapped in the receiving space.