Electrical Box, Box Type Masonry, Number of Gangs 2, Bracket Type -, Capacity 45.0 cu. in., Material Galvanized Zinc, Number of 1/2 In. Back Knockouts 4, Number of 1/2 In. Side Knockouts 12, Clamp Type -, Number of 3/4 In. Back Knockouts 4, Number of 3/4 In. Side Knockouts 12, Nominal Depth 3-1/2 In., Nominal Length 3-3/4 In., Nominal Width 3-25/32 In., Color Silver, Standards UL 514-A Listed, File E195978