SWC 55171-SVT 4" Oct Blnk xtns R 2-

2-1/8 in deep 4 in octagon plenum extension rings with (4) 1/2 in side conduit knockouts are used to provide added wire capacity to existing octagon (8B) boxes and serve as outlet boxes for surface conduits. Garvin electrical box extension rings prevent the labor-intensive removal of older outlet boxes connectors and devices when extra wire capacity is needed. Adapter slots on the bottoms of the extension rings allow an easy slide on attachment to existing electrical junction boxes.