Threaded Grounding and Bonding Hub, 3-1/2″, Zinc Die Cast
https://nsiindustries.com/product/threaded-grounding-and-bonding-hub-3-1-2-zinc-die-cast/
The Bridgeport 3-1/2″ Zinc Die Cast Insulated Threaded Grounding and Bonding Hub with Aluminum Lay-in Lug provides a reliable ground fault path to connect rigid and IMC conduit to an enclosure, eliminating an additional grounding bushing.