Closure device for an opening in a wall for fastening an object, such as an automotive vehicle seat

The present invention relates to a device for closing an opening passing through a wall and intended for the fixing of an object, such as a motor vehicle seat. The device is characterized in that it comprises a flexible blade (4) fixed to the wall (1) so as to be elastically pressed, in the rest position, under the opening (2) to close it, the blade (4) elastically moving away from the opening (2) when the fastening means (3) is introduced into the opening (2) to allow it to be locked therein. The invention finds application in the automotive field.