Boxes, General Purpose, Square, Brand or Series: Appleton, Type: 4 Inch Square Box with Knockouts, Dimensions: 4 x 4 Square x 1 1/2 Depth Inch, Volume: 21.0 Cubic Inch, Mounting: Plain Vertical Bracket, Side Conduit Knockouts: 6 @ 3/4 Inch, Bottom Conduit