Hard Strips (India) offers the following Hardened & Tempered Spring Steel materials :

Grades	C %	Mn %	Si % (Max)	S % (Max)	P % (Max)
C 55	0.50-0.60	0.60-0.90	0.35	0.025	0.035
C 65	0.60-0.70	0.60-0.90	0.35	0.025	0.035
C 75	0.70-0.80	0.60-0.90	0.35	0.025	0.035
C 80	0.75-0.85	0.60-0.90	0.35	0.025	0.035

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