... ,Gr4,Gr5(Ti-6AL-4V),Gr7,Gr9,Gr12, etc.2.Standard: GB,DIN, IFI,UNC,UNC,JIS, BS,BSW ,ISO3.Specification ... screw(DIN7380) the diameter min M3-max M8-----Other non-standard: Cross recessed pan head machine screws with collar, ,Hexagon nuts ... composition and Michanical properties like Tensile strength etcDimension measurements like Thread size,Height of head,Depth of socket etc