The instant invention discloses a receptacle having a shape along the width of its face that is flat in one plane and along its length that has a constant radius. The shape of the face of the receptacle allows for the proper seating of an inserted plug. The shape of a wall plate around the receptacle along a section which runs along its vertical axis defines a surface of positive first differential and zero second differential, comprised of a combination of splines drawn between points of varying distance from a datum plane. The surface has zero second differential when the rate of height increase of individual splines is constant. When ganged with a switch, the front surface of the switch follows the shape of the cover plate.