1.Incoloy 825 special alloy fasteners bolt and nut 2.Standard:GB, ISO, DIN, BS, ... (1/4-3inch) 1.Incoloy 825 special alloy fasteners bolt and nut 2.Standard:GB, ISO, DIN, BS, ANSI ... -M64(1/4-3inch) 1.Incoloy 825 special alloy fasteners bolt and nut2.Standard: GB, ISO, DIN, BS, ... 80.6. Hardness limit: 100HV~370 HVhex nut,Heavy hex nuts, flange nut, square nut and fasteners. Leading manufacturer in China.