Battery spring with wire diameter from 0.08mm up to 3.6mm Made of carbon steel, piano steel, SUS, alloy steel, iron, plat ... 1.Battery spring with wire diameter from 0.08mm up to ... , piano steel, SUS, alloy steel, iron, plated steel etc3.widely used in chargerrecorder,flashlight,calculator,battery charger,toy and other electric areas4 ...