1.5000lbs coupler 2.heavy-duty Iron Plate 3.Shaped by Hydraulic Pressure 4.Zinc Plating or Powder Coating Treatmen The trailer coupler is made of steel, and the specification: 2-5/16"XA 5000LBS.Heavy-duty iron plate.Zinc plating and powder coating treatment is optional. The packing is 1pc in a display and then 8pcs in a outer carton.Carton size: 50X38.5X41cm