... 65Mn,etc2)wire diameter:as customers' requirement 3)spring have good hardness and resistence to both high ... )application:hardware, plastic, toy, auto, battery, electronic communication, sofa, bicycle, lamps and lanterns, jig, switch, locks, gifts, ... do include extension spring,compession spring,torsion spring,and in shape,include coil spring,belleville sping,leaf spring,flat spring,ring spring. 6)Both ...