A method and apparatus for assembling and installing an outlet cover for an electrical outlet box. The apparatus includes a base having a rectangular mounting aperture for aperture adapter assemblies. To create the desired cover plate, the appropriate aperture adapters has to be selected and assembled to accommodate the desired standard electrical outlet such as a light switch or socket. A cover is hinged to the base by fitting hinge members on both parts together and thus enables the cover to swing forwardly and backwardly against the base. A planar lever and serrated bar is present on one side wall of the base, which is orthogonal with respect to the hinge axis. By retaining the planar lever at different serration on the serrated bar, the planar lever can hold cover at different height and thus adjusts cover plate assembly openings to accommodate various cord sizes.