... making compression spring, extension spring, torsion spring, bed mattress spring , flat control cable, etc.Diameter:0.50mm--8.0mmWire Rod Material:65Mn, 70#, 72A, 72B, 82BStandard ... , ISO14001, SGS , NANTONG FAMOUS BRAND , EXCELLENT-QUALITY METALLURGICAL PRODUCTS. steel wire , spring wire, high carbon spring wire,mattress spring wire