This is a pair of Brass Brake Rotor Weights. Pro-Line now has Brass Brake Rotor Weights for all of Pro-Line?s 1.9? Scale Crawler Fans! The Brass Brake Rotor Weights must be used in conjunction with Pro-Line 6 Lug 12mm Hex Adapters (#6292-00) and work perfectly with Pro-Line?s Pro-Forge 1.9? Aluminum Wheels! These Brass Weights mimic the look of Brake Rotors inside the wheel and are expertly Made in the USA using the latest in CNC technology. Put extra weight exactly where you want it with Pro-Line?s Brass Brake Rotor Weights!