Mounting for a module such as a door bell or loudspeaker fits onto a door letter box using a mounting frame

摘要

The front plate [14] of such as a letter box has an aperture over which a frame is fixed [10]. The module, eg door bell, [16] is secured to the frame by a security plate [12] that has lugs [34] that locate against matching features on the frame. A connector [22] fits on the plate.