... Spring steel stripe SK4 1.Thickness0.3-3.0mm2.Width25-380mm3.QualityGood quality5.FinishingCold rolled & annealed6.Material50# 60# 70# 65mn 50GrVa T8A T10A 60Si2Mn ... knives, blades, motor , deep red, automobile clutches, rolling doors, clocks spring, lock, footwear, textiles, and a variety of industry standard parts ... quality, in fact, the above raw materials industry of choice. Spring steel stripe SK4