... wire), mild steel wire, manganese steel wire, phosphorus copper wire, nickel-plated wire, zinc-plated wire, tin-plated ... resistant steel wire), bronze, copper, phosphorus copper, beryllium copper. Surface treatmentNickel-plating, zinc-plating, tin-plating, copper-plating, black Oxide. gold, ... checked by our special quality control to ensure the spring quality stable and precise before packing.We can’ ...