Product overview Black painted high carbon c67 c70 c75 steel strip Guangweiyouliang's black painted high carbon steel strip is processed by annealed and cold rolled high carbon steel strip size: thickness 0.5-0.6mm, material grade ck75 ck67 ck55 ck50, typically used for auto speaker, speaker's external cover, surface is painted as black to meet customer's demand and statisfied with request for anti-rust, hardness less than 32 hrc, with slit/ round/ square edge avaible, guangweiyouliang's black painted high carbon steel strip also used for stamping, washers, clips and other uses. Decription: Material grade: ck90 ck85 ck75 ck67 ck55 ck50 ck45 Width: 8-300mm thickness: 0.08-3.00mm Hardness: < 32hrc Edge: slit round or square