Application:
These extension rings with conduit knockouts are added to junction boxes to increase wiring capacity and provide access for additional conduit runs and electrical wire.

Advantages:
Garvin Industries’ extension rings prevent the need to remove old conduit boxes and wiring from circuits when additional wiring is needed. Their bottom mounting slots allow a quick installation onto existing boxes. Red painted extensions rings are also available for fire alarm circuit identification.

Field Names:
Extension rings, extension boxes, box collars, box extenders, box extension, plenum extension rings, fire alarm extension ring, plenum sandwich plate, 1900 extension rings, 1900 extension box, 1900 plenum extension, 4S extension ring, 4S plenum extension.