6 in threaded grounding bushings are used to provide a means of grounding 6 in rigid or IMC conduits. Garvin Industries lay-in lug style threaded grounding bushings make it easy to insert a grounding wire. They feature dual rated aluminum grounding lugs that may be used with both copper and aluminum grounding conductors. Their insuliner temperature is rated at 150 deg C and their construction ensures mechanical protection for the raceway. Threaded grounding bushings are made out of malleable iron.