Material? Pure/nature rubber material + brass center ring Size? 10kg/pc (green), 15kg/pc (yellow), 20kg/pc (blue), Payment Term? L/C at sight or T/T Description? Diameter: 450mm Thickness: 5KG-30mm/10KG-51mm/ 15KG-67mm/20KG 89mm/ 25KG 92mm Center hole: 50.4-50.8 mm Weight tolerance:+ 1.0% Package/Packing? 1pc/brown box, about 1,000kg/wooden case