Electrical Box, Box Type Square with Bracket, Number of Gangs 2, Bracket Type BOX-LOC Flush, Capacity 21 cu in, Material Steel, Number of 1/2 In. Back Knockouts 1, Number of 1/2 In. Side Knockouts 3, Clamp Type NM-B, Number of 3/4 In. Side Knockouts 1, Nominal Depth 1 1/2 in, Nominal Length 4 in, Nominal Width 4 in, Color Silver, Standards File E195978, UL 514-A Listed