... -7/8,3-1/2,4,4-1/2,5,5-1/2,6-5/8 3.Grade:E,X,G,S 4.Upset ... quality. The tensile and impact properties are verified by destructive testing for each process batch tool joints to ensure the quality ... Hardness: More than 285 HBImpact Text: More than 54 J 6-5/8"H tool joint