Prime Choice Auto Parts SMKPR4132941329976 Pair of Drilled and Slotted Rotors and Semi Metallic Pads Exceptional Performance Drilled and Slotted Brake Rotors Designed to obtain peak performance under all braking conditions Precise tolerances offer maximum performance, increased comfort, and extended longevity of all brake system components Machined surface to ensure synergy between the brake pad and brake rotor during the break in period Venting design (when applicable) increases overall brake rotor cooling and provides additional protection against thermal cracking