This 4-inch octagonal steel electrical box is constructed from corrosion-resistant galvanized steel, making it ideal for housing lighting fixtures, ceiling fans, or electrical connections. It features multiple concentric knockouts on the sides and bottom to accommodate various conduit sizes and configurations, ensuring flexibility and ease of installation in residential, commercial, or industrial settings. The box offers a capacity of 15.0 cubic inches and a depth of 1/2 inch.The PROSERIES 54151-K is a 4-inch octagonal electrical box made of galvanized steel. It has a capacity of 15.0 cubic inches and a depth of 1/2 inch. The box is equipped with 8 x 1/2 knockouts (4 on the bottom, 4 on the sides) and 4 x 3/4 knockouts (2 on the bottom, 2 on the sides). Its dimensions are 4 x 4 x 1-1/2. It is designed for new work applications.