Bushing for multiple sized and shaped holes in structural members

Abstract From the Canadian patent

A self-backing cable bushing for offsetting an electrical conduit passing through a knock out or opening in a structural member. The bushing has face and backing flanges connected by a living hinge. An annular tubular projection with peripheral ramp lugs extends from the face flange. The cable bushing may be installed by locating the face and backing flanges on opposite sides of the knock out and inserting the ramp lugs into the circular hole in the backing. This face retains backing flange in parallel closely-spaced relation with the surface of offset between them. The bushing may thus be used to protect an electrical conduit from contacting the edges of a variety of knock out shapes.