Socket Set Screws 12.9 grade are heat treated to meet or exceed ANSI B18.3and IFI standards. C37 to C44 Rockwell hardness. 180,000 minimum tensile strength up to 1/2" diameter. 170,000 on 1/2" and larger. Class 3A threading. Hi-Flow industrial grade quality cup points are standard any many other variations are avaible upon request; Cone,Flat,knurl,and Oval.