StopTech Sport Rotors are 1-piece direct replacement brake discs for factory brake systems and stock calipers. These Slotted and Drilled rotors provide improved cooling and better bite even under extreme conditions. Features a black e-coating for corrosion resistance and high-carbon metallurgy for noise reduction. This specific part number 127.33099R is a Right Side Front Rotor. Key Technical Data: Diameter 312mm, Thickness 25mm, Bolt Pattern 5x112. Components in this series: 127.33099R (Right Front Rotor), 127.33099L (Left Front Rotor).