Aluminum Extension Box For Use With 2-Gang Electrical Box/ OVERALL WIDTH: 4.500 INCHES NOMINAL INSIDE DEPTH: 1.000 INCHES NOMINAL END ITEM IDENTIFICATION: TRN44A OUTLET CABLE ASSY SPECIAL FEATURES: TWO - GANG EXTENSION - 4-1/2 INCH BY 4-9/16 INCH BY 1 INCH DEEP; THERE ARE MOUNTING HOLES ON TWO SIDES ONLY MATERIAL: ALUMINUM OVERALL STYLE DESIGNATOR: B4 RECTANGULAR-ROUNDED CORNERS