4" deep, 4" square junction boxes with (6) 1/2” & (6) 1/2”-3/4” side knockouts and (2) 1/2”, (2) 1/2”-3/4” bottom knockouts are for "cut in" old work applications when deep devices (speakers, strobes, etc.) are required to update a structure. They come with snap in clips and plaster ears. Garvin Industries’ labor saving design eliminates the need to awkwardly install boxes and extension rings to accommodate deep devices.