This product is made of fine quality stainless steel material, not easy to rust, clear lines. Features: Made of fine quality stainless steel material, not easy to rust, long-lasting to use. Deep thread, even tooth path. Smooth surface, no burrs, clear lines without skid. High hardness and corrosion resistance. Stainless steel material will not release toxic substances, non-toxic environmental protection. Specifications: Item type: Nut Material: 304 Stainless Steel Selection type: M-3, M4, M6, M-8, M10, M12(optional) Quantity: Package weight: M-3: 4g/0.14ounces M-4: 6.5g/0.22ounces M5: 8g/0.28ounces M6: 21.5g/0.75ounces M-8: 42g/1.48ounces M-10: 94.5g/3.33ounces M12: 131g/4.62ounces Package size: 1208020mm/4.723.140.78inches Package list: 5PCS*Nuts