Manufactured to mechanical specification SAE J78-1979 to achieve a surface hardness up to 650 HV to prevent torque shearing under load and a core hardness of up to 400 HV for improved ductility.
**Features** *No 2 self-drilling tip.|*Manufactured to mechanical specification SAE J78-1979 to achieve a surface hardness up to 650 HV to prevent torque shearing under load and a core hardness of up to 400 HV for improved ductility.|*Made from C10-18 steel.|*Plated in zinc 3-5 microns.