The black plastic thingie is probably a "strain relief" to protect the wires from rubbing against
the edges of the box. It is not necessary in most cases. You can replicate it with several turn of
black tape if you wnat to.

Bob Swinney
"stryped" wrote in message
...
I used the blue plastic Carlon boxes from home depot in the detached
garage. When I was puttign a new fixture in the hallway to my house, I
noticed a tan looking ceilign box was used and there was a "black
plastic thing" for lack of a better word inside the box against the
wires coing into the box.

What are those and were those needed in my detached garage with the
blue plastic outlet boxes? I did wire staple the wires within 6 inches
of the box.