Hubbell-Raco 187 Drawn 1-1/2-Inch Deep Square Box Extension for Switch Boxes

RACO 4 square x 1 1/2 Inch deep, drawn, extension ring to attach to a switchbox. Each side has two 1/2 in. and one 3/4 Inch knockout. The ring provides additional cubic capacity, and a means for connecting surface mounted conduit raceways.