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