Insulated Split Bushing, 3-1/2″, Plastic for Conductor Protection
https://nsiindustries.com/product/insulated-split-bushing-3-1-2-plastic-for-conductor-protection/
Use the Bridgeport 3-1/2″ Mighty-Rite Insulated Nonmetallic Split Bushing to protect conductors passing through conduit and to terminate rigid and IMC Conduits or rigid and EMT connectors to a box or enclosure before or after pulling conductors.