Copper Nickel Alloys, also known as Cu-Ni, offers excellent corrosion resistance, especially in marine salt water environments. Copper-nickel alloys that are generally chosen for sea water parts and service equipment contains 10 to 30 percent nickel. These various alloys also have important additions of iron and manganese which are necessary to maintain good corrosion resistance in the harsh environments. Aside from being very corrosion resistant to sea water, copper nickel alloys are very thermally stable. Copper nickel is most commonly used in applications such as electrical and electronic products, tubes for condensers in ships and power plants, various marine products including valves, pumps, fittings and sheathing for ship hulls.