Insulated Split Grounding Bushing, 3-1/2″, Steel with Lug
https://dev.nsiindustries.com/product/insulated-split-grounding-bushing-3-1-2-steel-with-lug-2/
Use the Bridgeport 3-1/2″ Mighty-Rite Steel Insulated Split Grounding Bushing with Aluminum Lug to install bushings to 3-1/2″ rigid or IMC conduit or EMT fittings before or after wire pull-through.