Device for filling at least one fuel tank installed in a motor vehicle

The device has corrugated pipes (4, 6) connected with filling connecting pieces and/or tank connecting pieces (7, 8) at ends by a coupling unit (9). The coupling unit includes a coupling element (10) that is associated to the corrugated pipes, and another coupling element (11) that is associated to the filling connecting pieces and/or the tank connecting pieces. The coupling elements are coupled with each other by a plug connection, and locked relative to each other in a position by a form-fit locking element (26).