Electrical Box Box Type Masonry Number of Gangs 1 Bracket Type - Capacity 22.5 cu in Material Galvanized Zinc Number of 1/2 in Back Knockouts 4 Number of 1/2 in Side Knockouts 8 Clamp Type - Number of 3/4 in Back Knockouts 4 Number of 3/4 in Side Knockouts 8 Nominal Depth 3 1/2 in Nominal Length 3 3/4 in Nominal Width 1 31/32 in Color Silver Standards File E195978 UL 514-A Listed