Electrical Box, Box Type Masonry, Number of Gangs 3, Bracket Type -, Capacity 47.8 cu in, Material Steel, Number of 1/2 In. Back Knockouts 3, Number of 1/2 In. Side Knockouts 10, Clamp Type -, Number of 3/4 In. Back Knockouts 3, Number of 3/4 In. Side Knockouts 10, Nominal Depth 2 1/2 in, Nominal Length 3 3/4 in, Nominal Width 5 19/32 in, Color Silver, Standards UL File E195978