spring steel bar Grade: GB: 65Mn ,55Si2Mn , 60Si2Mn ,55CrMnA ,60CrMnA ,50CrVA, 60CrMnBA,55SiMnVBA , 60Si2CrA spring steel barWe are making the spring flat steel bar all the time ,the detail information ... is as flw :1,Grade: GB: 65Mn ,55Si2Mn , 60Si2Mn ,55CrMnA ...