Abstract: A wall plate for snap-fit engagement with an identical wall plate on one or both sides to provide an assembly of side-by-side plates for use with a ganged installation of electrical wiring devices. The plate is rectangular with a rearwardly extending flange, including a pair of side walls having inner and outer surfaces, extending about its periphery. A U-shaped tab, having a medial portion including a linear-edged shoulder parallel to and spaced from the adjacent side wall, extends outwardly from the outer surface of each side wall. A rectangular opening in each side wall is positioned laterally opposite the tab on the other side wall. As two plates positioned with the rear edges or surfaces of their flanges in a common plane are moved linearly toward engagement of the outer surfaces of opposing side walls, the tab extending from each opposing side wall is received in the opening in the other side wall.