Model: NFHS. Size: M3 M4 M5 M6. Preferred Stainless Steel, High Temperature Resistance, High Strength, Strong Torque. Material: Stainless Steel. Plate Hardness: HRB70 or Less. Head Shape: Hexagon. Pressure Riveting Operation Must Use the Punch, Pressure Riveting Machine, Can Not Be Knocked!
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