SWC 55171-BLNKSS 4Inch Octgon Blnk

2-1/8 in deep 4 in octagon plenum extension rings with blank sides are used to provide added wire capacity to existing octagon (8B) boxes and provide access for additional conduit runs. 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.