1065 spring steel strip thickness: 0.05~45mm width: ... platerstensil strength:1100 to 2000 N/mm2Tempered spring steel stripMaterial grade: c50,c55,c60,c67,c70,c75 ... ,white,polished,nature,grey,black Hardness: 40-55HRC for hardened and tempered treatment. Edge: slit, round, ... for standard sea worthy Application: metal parts,construction tool,agricutural tool,roller shutter spring 1065 spring steel strip