4 sq-in extra deep Junction Box with (8) 1/2 in and (4) 1/2 to 3/4 in side knockouts and (3) 1/2 in, (2) 1/2 to 3/4 in 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.