The life of the “wire”, is actually “low carbon steel wire”, carbon content in less than 0.2%. The surface is usually coated with zinc plating because it is easy to rust. Under atmospheric conditions, the galvanized layer will not rust before most of the fall off, relatively soft. The life of the “steel wire”, is carbon content in about 0.6% of the “carbon steel wire”, or carbon content in about 0.8% of the “high carbon steel wire”, they have enough hardness and elasticity after appropriate heat treatment, high strength. Uses such as winding ordinary spring and so on.