56 Drawn extension ring is suitable to use with 4-11/16-Inch square steel box. It features 0.062-Inch steel construction and has pre-galvanized finish. It measures 4-11/16-Inch x 4-11/16-Inch x 1-1/2-Inch. Extension ring with 12 knockouts, includes eight 1/2-Inch side knockouts and four 3/4-Inch bottom knockouts. It has 29.5-Cubic-Inch capacity. This square ring provides a means for adding cubic capacity or as an outlet box for surface conduit. Extension ring is UL listed and CSA certified.