Cast Iron Dock Bollard Marine bollards are mainly made of iron, steel, ductile iron or stainless steel. It uses the technics of precision cast. For the material of iron, we suggest our customer to choose the ductile iron for it has higher strength, better toughness and ductility than common casting iron. It also has good wear resistance and vibration absorbtion. Our bollards are produced strictly complying with industrial standard. They have high stability and do not have any defects. All the bollards get the approval of ISO9001 and CCS certificate. For more detail information, please feel free to contact us.