Conduit Bushings with Ground Lug and Insulated Throat 4" - Zinc Die Cast - Conduit Bushings are Used with a Locknut to Terminate Threaded Rigid and IMC Conduit to a Box or Enclosure and Connect to Ground Electrode.Grounding Bushing with Insulated Throat with Aluminum Ground Lug - Zinc Die Cast 4" features include: Used with a locknut to terminate threaded Rigid and IMC conduit to a box or enclosure Lug provides for bonding jumper to a neutral bus bar Thermoplastic liner prevents damage to wire insulation Set-screw provided with each fitting locks bushing in any desired position Resists corrosion, chemicals, and temperature extremes Die Cast Zinc UL/CSA Listed Order Qty of 1 = 1 Piece Below is more info on our Grounding Bushing with Insulated Throat with Aluminum Ground Lug - Zinc Die Cast 4"