Ductile Iron Manhole Cover D400 has high strength and toughness, making them 30% lighter than grey cast iron manhole covers of the same type. Ductile iron is used to make ductile iron covers for manholes. Casting is more efficient, and ductile iron machining is less expensive. Apart from this, Ductile Iron Manhole Cover D400 is tested under various parameters to ensure its high quality and effectiveness. The surface of the ductile iron cover is treated with asphalt anti-rust paint. This requires very low maintenance and replacement costs.