A mounting frame facilitates the installation of ganged electrical devices into a single switchbox. The frame is a rectangular plate with a rectangular opening and provides a rigid support for the devices. Support is needed when the wall on which the devices are to be mounted is not planar or when the...http://www.google.de/patents/US5178350?utm_source=gb-gplus-sharePatent US5178350 - Mounting frame for ganged electrical devices
