1) Material: Fe, lead-free to comply with European standard 2) Used on passenger car steel wheels and alloy wheels 3) ZN plated and then Nonpoisonous Coating, (after that polymer coated if ordered) Salt-spray tested to resist corrosion for more than 480 hours. 4) Weight size: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60g