Electrical Box Box Type Square Number of Gangs 2 Bracket Type BOX-LOC Flush Capacity 21 cu in Material Galvanized Zinc Number of 1/2 in Back Knockouts 5 Number of 1/2 in Side Knockouts 9 Clamp Type - Number of 3/4 in Back Knockouts 2 Number of 3/4 in Side Knockouts 3 Nominal Depth 1 1/2 in Nominal Length 4 in Nominal Width 4 in Color Silver