To supply brake drums from China. Materials:grey cast iron, Surface treatment: zinc-plated or spray-painting . Brake Dia.:160mm,250mm,203mm,200mm,250mm,Shoes width : 35mm,40mm,50mm,Number of Studs : 4 or 5,Stud Size : 7/16",3/8",M12,M14,5/8",PCD :101.6mm,165.1mm,152.4mm,139.7mm,165.1mm,Brake Type: Knott. If you are interested in trailer brake drums, Welcome to your inquiry.