Brake Rotor (Disc)

The cast iron or carbon disc that brake pads clamp against. Slotted rotors release gas and water from the pad surface. Cross-drilled rotors (popular but cracking-prone) reduce unsprung weight but can fail under sustained track use. Two-piece rotors with aluminum hats reduce thermal mass and unsprung weight — standard on factory NISMO and TRD-tuned cars.