StopTech Sport Rotors are 1-piece direct replacement brake discs for factory brake systems and stock calipers. The 127.47012L is a Left Front Drilled and Slotted sport rotor that provides improved cooling and functional styling. The cross-drilling and slotting helps wipe away debris, dissipate heat, and improve wet weather braking performance. This part number refers to a single left-side rotor. For a complete front axle set, it is commonly paired with: 127.47012R (Right Front Rotor).