Spring steel strip Steel grade 65Mn,1065,SAE1055,1045,CK50,CK55, CK60,CK67, CK70,CK75, C75Cr1,50CrV4, 51CrV4, 60Si2Mn, etc Thickness 0.08-4.0mm Width 3-400mm Hardness <200HV, 200-300HV, 300-550HV Edge slit edge; both rounded; one side round, one side slit; square etc Surface polished (blue, yellow, white, grey-blue, black, bright) or Nature etc Tolerance thickness +/-0.01mm max; width +/-0.05mm max Physical propety Tensile strength: 450-1850N/mm2 Mobile/whatsapp +86 13853842286