UPGR8 S-Series 20 Pieces Steel Closed Ended Wheel Lug Nuts with Key (M12 X 1.5MM, Blue) Weight: 36g per lug nut. Length: 35MM. Precise fitment for best result of installation. Unique Design help preventing wheel from scratch. Heat-treating offers more strenght and lighter weight,Track and race proven durability and quality. To prevent scratching when installing lug nuts, make sure to install and tighten all nuts by hand as much as possible before sliding on the provided socket. Power tool/air tools are more likely to scratch lug color then a standard wrench.