Add-on housing

The present invention relates to a mounting housing for example for circular connectors. For a convenient pre-assembly of the mounting housing it comprises an access opening which can be closed by means of a cover. The cover is hooked in a housing body of the mounting housing on one side and is secured at the housing body via a retaining nut, with the cover in conjunction with a seal arranged in the area of the access opening sealing same. In addition, a vibration protection is provided in that the cover comprises a contoured area which in the screwed on condition is urged by the retaining nut against a corresponding area of the housing body. The mounting housing also comprises a mounting flange which is formed at the housing body in such a manner that an installation and removal of the mounting housing at corresponding mounting surfaces is possible after the pre-assembly of the mounting housing.