Electrical Box, Box Type Square, Number of Gangs 2, Bracket Type -, Capacity 30.3 cu. in., Material Galvanized Zinc, Number of 1/2 In. Back Knockouts 3, Number of 1/2 In. Side Knockouts 12, Clamp Type -, Number of 3/4 In. Back Knockouts 2, Number of 3/4 In. Side Knockouts 8, Nominal Depth 2-1/8 In., Nominal Length 4 In., Nominal Width 4 In., Color Silver