... order grade : SUP 5, SUP6, SUP7 , SUP9 , SUP10 spring flat steel Name: spring steel flat bar Material : 65MN,60Si2Mn,55CrMnA,SUP7,SUP9 ... /T 1222-2007 Becauses of Our foreign guests demand for the bulk of spring steel flat bar, So our company prepared a ... different size of the various conventional spring flat! As the export needs,So we asked for the good material! high quality control ...