1-1/2" deep 4" square extension ring Outlet box, 1/2" knockouts

T&B Steel City 53151 1/2 3/4 Silver Pre-Galvanized Steel Square Box Extension Ring, 4 Inch L x 4 Inch W x 1-1/2 Inch D

Item #:E325-25:Replaces Part #:'s : 6487